LEGAL ("Real Money Trading") Games
* Entropia Universe      

Entropia Universe (formerly Project Entropia) is one of the few MMOs that explicitly allows both the purchasing and cashing-out of in-game currency. Of course, the exchange rate is way more favorable to putting money into the game than taking it out, to the tune of a 10:1 ratio. And there's also a minimum 1000 Entropia Dollar threshold to withdraw your money with a 1.5% withdrawal fee. So you'd need to earn a minimum of 1000 Entropia Dollars to withdraw $98.50 USD ($100 less the 1.5% fee). 

Full disclosure: I have not played this game personally. However, everything I have read about it seems to indicate it takes significant financial investment to actually turn some sort of a profit in it. The issue is that there's really not a mechanism for doing free things and then turning that time investment into actual money. Nearly every game activity, such as combat and mining requires expendable resources that can only be obtained by buying them with your own money (the ultimate "freemium" game, so to speak). Thus it's not under the "Grinding for Cash and Prizes" heading. 

So this really appears to be more gambling-tilted than anything else, unless you have some sort of in-depth insider knowledge before you start of how to multiply an initial investment. That's actually an intriguing possibility, but only if you have free hundos/thousands in the bank to play around with that you don't mind potentially losing! Do bear in mind that this is also, in effect, tantamount to unregulated gambling, and there's legally little stopping the developers from actively tilting the odds further against you if they feel you're taking too much money out of the game. 

It does at least appear to be stable, however, as it has been online since 2005 and seems to consistently add new game areas every couple of years. 


Links Out: 
- Good review that gives an idea of what the game actually costs to play (GiantBomb)
- Entropia Directory wiki
- Another detailed review with useful comments (Skeltoac - someone's personal site)


* Second Life          
 Second Life is kind of a combination of "Grinding for Cash & Prizes" plus the long-term investment opportunity / speculative gambling with actual money that something like Entropia Universe offers. 

 It's basically a giant sandbox world, in which players create a custom avatar, and then can create custom objects by using a 3D modelling system to put them together from basic in-game parts. You can build vehicles, huge structures, etc. as well as clothing and accessories for other characters. There aren't any real "game" objectives a la the standard MMO, like grinding or quests, though players have some ability to create things like that on their personal land if they choose.
 The game's currency is the Linden Dollar, and these can both be bought with real cash and also extracted to real cash. The game's big money is in either selling and renting real estate or creating objects for sale apparently, but it's also possible to grind out smaller amounts of Linden Dollars through paying work and games.
 As with any MMO, of course, up-front fees should be discussed before going any further. A basic Second Life account is completely free, with this account you create an avatar who can wander the world freely, and if you want to dabble in creating objects there is a community sandbox area where you can build them (and you are allowed to sell them once completed). If you want to get into owning, developing or trading in land, however, you'll need the Premium Account, which is a $9.95 USD month-to-month subscription or $72 for a year if you're willing to commit in advance. There are also fees for purchasing land, land maintenance, and a small transaction fee for any changing hands or cashing out of Linden Dollars except for buying them direct from the publisher's store.
 The game is available for Windows, Mac or Linux, and doesn't have real beefy system requirements but does recommend 3 GB of RAM and a decent dedicated graphics card. It's one of the longer-running virtual worlds (started in 2003) and seems to be safe to at least experiment with a free account to see what you can do.
 Links Out:
 -  Get a taste of Second Life with Dunkey 
 -  Good introduction to the basics of the game (Engadget)
 -  Good introduction to in-game moneymaking (Doughroller)
 Useful Supporting Products:
Sybex Official Guide to Second Life Scripting
Scripting recipes (templates) for many types of objects
 *  Pet Pack 

 * Wurm Online       

 Wurm Online is an MMORPG that has formally allowed external selling of gold and items, but does not have any internal mechanism for doing so. You have to arrange your own deals externally of the game and it's both buyer and seller beware when you do. 

 This is actually a project that Notch started working on pre-Minecraft, though he left it in 2007. Development started way back in 2003 but was just released in 2012. Some people seem to insist on it being called a "survival MMO" rather than an MMORPG, but to me that seems semantic hair-splitting -- you've got statistics, you level up, it's a Tolkein-inspired fantasy world, etc. The "survival" bit comes from rolling in some elements of Minecraft, such as constant thirst and hunger meters to be attended to, the need to provide your own light source in any unlit area and a strong emphasis on mining raw materials to craft stuff. 

 Wurm differs from Entropia Universe in that though it is a little more demanding than the usual WoW format, you can still play it like a standard MMORPG and acquire items and money that you can then sell for real cash without worry about losing your account. Not everything is a consumable and needed in-game stuff like weapons and armor don't have to be replaced by getting out your credit card. The only issue is safely arranging your sales. 

 You can start the game with a free trial, then move to a monthly subscription fee of eight Euro (or about $10 a month for US players depending on current exchange rates). Another option is Wurm Unlimited, the standalone version which you just buy at retail for a one-time fee, but uses player-created servers rather than the official servers (Wurm Unlimited characters CANNOT transfer to the Wurm Online servers, but it looks like it might be a good practice tool before rolling onto the official online servers.)  

 Links Out:
 - Basic Knowledge (Wurmpedia)  

* Steam Workshop Games (Team Fortress 2, Dota 2, CS:Go and more)       
 These games are locked to Steam, which means that in-game items you unlock through various means can be bought and sold in the Steam Marketplace ... but cash money only goes into the Steam Wallet, as of this writing it can't come back out, so going this route is simply earning Steam Fun Bucks with which to buy Moar Games and Moar Hats. As we discussed with Steam Cards in the "Grinding for Cash and Prizes" section, there's still a potential way to flip this into actual money by creating a new account and then selling it, but we're also almost certain that Steam doesn't actually allow this.
 So what's the legal way to make real money with TF2 et. al? HAT CREATION. If you have some skill at modeling 3D objects, you can use Steam Workshop to create new hats and items for the game. You submit your created items to the Valve Overlords, and if they approve them and add them to the game, you get a share of the revenue on all future sales through the Mann Co. store.
 The catch here is that the people doing this are usually professionals who already work as some sort of graphic or object designers in the game industry. But hey, maybe that's you. An early 2015 article from Venturebeat indicates that there were about 1,500 creators with published objects, and the average annual revenue for them was about $38,000 USD -- a pretty decent salary for a single person in the U.S. unless you're living on the Spendyfornia coast or in New York City. Certainly a nice little supplementary income at the least.
 Want a complete list of Steam Workshop games you can create revenue-share items in? Sure you do. This is them, current as of early 2016: Team Fortress 2, Dota 2, Counter-Strike: Global Offensive, Dungeon Defenders, and Eternity and Chivalry: Medieval Warfare. Keep an eye on   this page  for further developments.
 Links Out:
 -  Steam Workshop 

* Star Citizen (PC)

Star Citizen is the long-developed, sprawling and highly confusing space MMO project from Wing Commander designer Chris Roberts, which is apparently going to be like Wing Commander: Privateer meets Mass Effect when everything is done. First announced as a Kickstarter in 2012, development has dragged out for years and as I write this at the end of 2018, the full game is still not available and the release date is still unknown. 

However, various playable "modules" have been dribbled out over the last few years, each representing one of the game's modes of play - a ship customization and maintenance module, spaceship combat, FPS combat and so on. All of this stuff coalesced into the Universe alpha module in late 2015, which is basically a limited playable version of what the full game will eventually be - basically a demo version with one planet and several moons to toodle around on. 

Though it's incomplete, a significant real money trading economy has already sprung up. In fact, this started before anything was even playable. Early trading centered on the fact that original Kickstarter backers got "lifetime insurance" on any ships they bought, basically meaning free respawns (whereas other players lose destroyed ships entirely a la EVE Online). This is basically a status perk assigned to a ship once bought by a Kickstarter backer account, however, so these people could sell and trade them to others at a HIGH price

The playable alpha has expanded the real money economy. There isn't a huge amount to do in it as of this writing, but in addition to ships it has added all sorts of other resources to mine and grind for. The important thing here is that the official stance toward the real money "grey market" appears to be one of tolerance by the developers, so long as it stays outside of the game world. Transactions arranged openly through third-party sites don't seem to have repercussions for players, at least judging by trading activity on sites such as Reddit. 

Interestingly, this all makes the game kinda like the high seas of the Age of Sail. Lose your in-game cargo ship and you can lose everything, and since this is an alpha build you can crash thanks to simply de-syncing with the server or hitting a glitch (like an unexpected storm at sea). Also, pirates are a thing. Some players are actively targeting traders and demand in-game currency fees for safe passage. The game is designed such that people can even physically sneak onto your ship and jack it when you dock. 

No way to know if this will stay the same when the full product is finally released, but it's the way the alpha has been run for years now. The alpha is available to anyone to play but requires a one-time purchase of a "starter pack" that gives you a ship, three months of assplosion insurance and some in-game currency for $45 USD. Of course, this also buys you access to the full game when it comes out. 

Links Out: 

* Shroud of the Avatar (PC)

Shroud of the Avatar is the low-key follow-up to Ultima Online; low-key because designer Richard Garriott created it with his new company Portalarium, but EA still owns the rights to Ultima (and is still operating the original Ultima Online as of this writing).

In as far as I can tell, real money trading is explicitly allowed according to this official forum post. Deal-making just has to be kept out of the actual game and confined to the Player Marketplace section of the official forum.

There is a bit of marketing misdirection involved with this game that you should understand before jumping in. Around October of 2018 they decided to start running banner ads declaring it "free to play." It isn't, however. The game has always had a limited free trial mode that restricts you to level 50 and prevents you from trading. They simply started advertising that same mode as "free to play." To be able to trade and get the full experience, the game requires a one-time $20 purchase (see Amazon link below).

Links Out: