iFunSpace 5

This is a pretty good gaming site with some classics like Bookworm, Crazy Coins, Big Money and even Pacman that you can play for free on your browser of choice. The flash games are simple but fun and you can choose from categories like arcade, puzzle and bain games. A nice way to spend an afternoon without having to download or install stuff.

if you're more into making a buck though, you can always get an account and go for it playing bingo and slots, or even go toe to toe with other arcade players in high score challenges. The best part is teasing them when you beat their score :)