Well, it ain’t no Desktop Tower Defense (to which poor, unsuspecting Jeremy got addicted), but you may find you enjoy Juggler, a simple but tricky flash game. Work less, play more.
UPDATE: Er, whoops. Link included, so that you can actually play the game.
DarrenBarefoot.com 
There is one teeny tiny addition you should make to this post.
The link to Juggler!