Travian

http://www.travian.us/

I'm addicted. It's a strategy Browser Game (Like Neopets (The game isn't like Neopets, but Neopets is an example of a Browser Game), you don't need to download anything) where you command a Village and have to make sure your village is okay. Me and a group of my friends are starting an Alliance (a group of Villages that protect eachother). I have two characters; 01 and 08. 01 works on a trading system (so we aren't in so much debt all the time), and 08 works on the Alliance (so we can trade)

Fun. Addictive. Long-term. Blah.