Lets start out with one of the best Freebies out there at the moment in the form of Fiesta.
this is a deceptively deep somewhat cartoon/manga style MMO with more that a slight nod to the styling of Dragonball Z & Blue Dragon and other eastern animation.
The basic needs in terms of processing power and RAM of the game are on par with World of Warcraft and its basic interface take most of its nods from this hugely popular game.
Leveling and progression are on a relatively easy learning curve and the community is lively and vibrant with a fairly welcoming attitude to new gamers. More than worth the download and occasional laggy gameplay and login.
Ok onto Maple story, if you dont know what this is by now you have no good reason being on the internet. If however i must describe this anime come to life MMO i would call it an early Zelda brought to the world of MMO's if Nintendo had a one night fling with the Mistwalker team and had raised there bastard son as a MMORPG.
All the classic genre specific mobs and classes are there and offers little in the way of surprises in any way to a seasoned RPG player. Worth the download if only for the music and dawwww.
And now the big boy of the free MMO world. SRO has been established as one of the most adult and mature free MMORPG's of the last five years. Set in the 18th century almost entirely on the Chinese silk road you take one of several traditional roles after achieving the profession level requirements, this means you start off as a generic all rounder capable of pretty much anything you choose. Unlike most other free games SRO has a unique in game monetary system in the form of both traditional money and SILK. Silk is a unique way to negate gold farmers destroying the in game economy as the company itself submits to "gold buying" in an official capacity. By selling silk you gain the ability to acquire uniquely powerful items in game that even the most frantic of gold farmers would be hard pressed to find and impossible to sell on. All in game trade is done by the players themselves, at a set level you gain the ability to set up a stall anywhere you wish and sell your goods at whatever price you wish this results in a unique player based economic twist that can see some real bargains for smart shoppers.