http://www.coffeebreakarcade.com has tons of great, free games. Bounce Out, Insanaquarium, Big Money, Dance Floor Dominator, Bookworm, Noah's Ark, and Golden Gate Drop are just a few of my personal favorites. The site is easily divided into six sections of games: Classic, Cool, Shooting, Sports, Casino, and Racing, and it's also searchable.

http://www.neopets.com is a great game site. You have to sign up to play, but the games are definately worth it. There are three kinds: Action, Puzzle, and Luck/Chance. There's even a Featured Game that changes daily for double points. There are over 100 games to play, including Carnival of Terror, Extreme Herder, Faerie Bubbles, Grand Theft Ummagine, Ice Cream Factory, Meriball, Cellblock, Snow Wars, Kacheekers, Cheat, and many more.

http://www.nick.com features games starring many of your favorite Nick characters. These games aren't just average hero-on-a-mission games. With these games, you can cook up a Krabby Patty, run through the mall avoiding guards, eat junk food, fling baby food at monkeys, color a tattoo, snowboard, race through a mine tunnel, and care for wild animals. Not to mention that this is the only site with Clickamagigs, the most fun your mouse will ever have with a few clicks.

http://www.shockwave.com is not only where you can download tools to actually play games, but play some original games only at shockwave. Collect ingredients for burritos, become a knight, explore space, raid a cookie factory, attend an intergalatic college, and much more here.

http://zoogdisney.com is a great site for games. Play as your favorite Disney characters in a variety of games. Learn kung-fu with Matt, make sandwiches with Stitch's cousin, catch frogs with Raven, make burritos with Rufus, run from evil pigs with Dave, mix it up with Sticky, design clothes with Lizzie, do your nails with Miranda, collect money with Corey, and lots more.