Gotta love Newgrounds. They never fail to entertain in the game department. Here's a favorite of mine: http://www.newgrounds.com/portal/view/529334
Yeah newgrounds does always deliver.Though yesterday I just ended up playing other games on my laptop while crafting on this computer. lol
ArmorGames.com has some really good ones. I liked Kingdom Rush - It's one of the best Tower Defence games on the web.
I must admit I even played Pinball on my old laptop for several hours while listening to iTunes.. I am too easily amused...
Sounds like me on my Steam account! Except most often I'm staring at my Library going "I'm bored." or " Too many to play; can't figure out which ones I want to play."
Steam? I've got the 'too many games; can't decide!' problem there myself. And I second the armorgames recommendation. I play stuff there all the time. Mostly puzzle genre, but occasionally others.