I have been playing Manyland (manyland.com) for over a year now and can honestly say this game is the best free online game for artists and programmers. This game is seriously fun and addictive. particularly if you love to create, draw, explore or just chat with silly fun people of all ages! If you have ever seen the 'Lego Movie', I would make a comparison that Manlyland is comparable to the chaotic land of creators featured in the movie, with the occasional custom area of order and beauty.
Manyland is the wonderful creation of game programmer and artist Philipp Lenssen, 'the creator', which features custom made pixel drawing programs which can be coded to animate or even to create custom mini games similar to early nes games. Philipp is constantly adding new features and keeping in touch with players to get their feedback. Att one time you could play and chat with him in person in the game. but recently it has become impossible for him to play as he is mobbed by players with praise and ideas.
I am an adult player and have many adult friends, even grandparents, and get occasional responses from people that this game is a 'kids game'. I will say this game does look like a kids game with the cute pixel fan art and adorable custom made avatars, but I honestly would not let my child play because of the uncensored chat, rampant teens trying to 'date' and occasional troll with some serious bad language and attitude. Since Manyland is extremely vast (you can take an elevator across the land for over 40 mins and not reach the end, potentially infinite) it is near impossible to moderate effectively. The players instead will monitor themselves with a down-vote and flag system which is usually pretty effective at getting rid of trouble makers and inappropriate creations.
Part of the joy of playing this game is exploring amazing hidden areas (which are often spread by word of mouth only) and collecting and sharing your favorite creations and avatars. Some of the art made by players is beyond professional quality, and is worthy of framing, which should make any game developer company extremely jealous that this art is provided absolutely free, just for the love of creating. Currently the only source of income Manyland gets is an occasional ad when you die, or spawn to another area, and they can be turned off if you wish. This game is a real hidden gem and community based game, and is the only game that has been able to hold my attention for such a long period of time due to it strong creative and ever changing element.
(Note: 'look at me i'm a cute internet girl' skin... those are cloneable bases I made.. also the the pink cute girl in stock pile that she comments on, haha. Go me!)