Seth got me to join this the other day: EverWars! It’s a text-based fantasy MMRPG and it’s pretty simple to play (once you find a browser that works — Yay, Mozilla!). You make a character. You attack other players. The game prints out a few lines of text describing how your battle went. If you win, you get XP and gold. If you lose, eh. You can be attacked even if you aren’t there (you get the XP for wins, but not the gold). You can use your gold to buy items or training. You can attack once every 30 minutes (but if you can’t play for say, 8 hours, you can then play 16 times at once).
That’s it. Nothing really to it. It’s easy to play and doesn’t take a lot of bandwidth (or thought — fun anyway).
If you join by clicking on my link, you become by squire. I’ll get gold every time you level up.
Off to work!