The other day I was completely bored at work so I started digging through web games and I found what has probably become my favorite web game ever:
Vector TD.It's a tower defense game, so you set up defensive turrets to defend increasingly powerful assaults. There are different enemy types, several different towers, and a few commands to mix them up. It's a lot of fun and makes it really easy to loose an hour or two while setting up the perfect gauntlet. It also doesn't hurt that it looks great with the whole retro/glowly look.
