http://www.furcadia.com/
I'm going to try and give a brief description of Furcadia. It is a low-resource mmosg client that can be used for things as simple as chat meetings or as complex as making games with the top screen. People have put their heads together and made some great dreams, but the great thing is that you can make your own. Even greater is that it's actually free. (Well, you pay money if you're interested in your avatar having wings, or being a dragon, gryphon, or phoenix, but it obviously isn't required.)
I've been using Furcadia for a long time, most of my buddies are in a Pokemon dream (don't laugh, the avatar art is great :P) so I basically stay there all the time. Besides the main maps in Furcadia, you can dream hop. There are dreams for everything you can think of: medieval roleplaying, Star Wars, Harry Potter, Final Fantasy, Kingdom Hearts; I've seen a lot of things, original and fan-dreamed. (Though, I haven't seen an Oddworld yet!
)
Here's a screenshot from early this morning (don't worry about the dreamstats I had recently triggered, everyone's at school now and I was pretending to still be asleep).
So, you choose an avatar, choose its colors (that can be changed any time), and you even get a little profile description that can come up whenever someone clicks you up on the screen. The portrait on the left-hand side comes already with the avatar, usually, but if you want a custom one like the one I have in the screen, you can get an artist to do it for you, or draw it yourself.
I think it was first meant for kids ages 10 and up to use, but the majority of the people I have met on Furcadia seem to age 14 and up. In other words, it's easy to learn and use, so I guess if you're lazy like me it's worth taking advantage of.
You can start playing around with it, heck, if you're really interested, you can get it now and I can show you basic controls.
Private message me if you have any questions or suggestions. I'm going to start working on avatars. :d