ArmorGames (http://www.armorgames.com)

There are games of every stripe on ARMORGAMES.COM: action, adventure, dress-up, sports, puzzles, and even versions of arcade classics like Pac-Man and Frogger. There's also blackjack, poker, and slots, but only virtual money plays on this site. In a rush? Try Four Second Firestorm, Four Second Frenzy, or Four Second Fury. The trio contains dozens of "microgames" lasting four seconds each, requiring quick thinking and quick fingers. And, despite the impolite title, The Idiot Test -- a challenging and funny series of brainteasers -- is a blast. With hundreds of free games to play online or download, this site is the ultimate procrastination station.

Many of the games seem to be aimed at adolescent boys with content that's a bit risqué or in bad taste (in one game, you have to pelt a dog with footballs before it attacks you and draws blood). This content -- especially the violence -- makes the site iffy for younger teens.

Online interaction: Registered users can chat and post comments. The site forbids strong language, but it probably comes through occasionally. The site encourages friendly, safe-for-work interactions and reminds users that kids visit the site.