WoW is very addicting, but fun. Something your kid will enjoy, meet new folks, and possibly join a clan/guild (people who play the same game and make a 'team' together). This might help keep them off the streets and out of trouble. I'm a gamer myself and I enjoy it very much.

Myspace is also good if they've got friends that have it as well, but make sure they know it's best not to add total strangers or people who think they know them, UNLESS they know them in person (in real life!). It can help them communicate with their classmates, friends, and family members. Myspace can also be addicting.

With both make sure they know not to give out personal information. Can be dangerous either way. The internet is a crazy place.