A couple of Browser "games"

If your a fan of football, thats AMERICAN football for all you overseas, you may want to check out GoallineBlitz. Its a stats based MMO with a rather large community. If you do decide to sign up please use this link.
http://goallineblitz.com/game/player.pl?player_id=359897

If your a person who enjoys Role Playing and Political intrigue, you may want to check out Nation States. Its a Text based Nation building "game" with another large following.
http://www.nationstates.net/

I play em both and enjoy em, also didn't see a mention of them here so I figured I'd drop a links.

AN web based game, where you lead roman city, Live the ancient world!
The sound of the sea, a white sandy beach and sun! On a small island somewhere in the Mediterranean, an ancient civilisation arises. Under your leadership an era of wealth and discovery begins. Welcome to Ikariam.

Dutch
http://ikariam.nl/

English
http://www.ikariam.org/

American
http://www.ikariam.com/

or you can play a vampire/werewolf game.. where you attack others, train skills, buy defense and much more, mmorpg:)
www.monstersgame.co.uk

if you love me, show it by clicking this link, it helps me in the game with some money:)
http://world5.monstersgame.co.uk/?ac=vid&vid=59244700