Snake is an old old game, but it's still great fun to play. And very simple too, just guide the snake to eat the food and avoid crashing. The more food, and the "fresher" the food is, the longer the snake grows.
Or play head to head against a friend or the computer. Can you make your opponent crash while not crashing yourself?
Snake is completely free to download and use.
Snake is a program for Windows 95, 98, ME, NT4, XP, 2000, 2003, Vista and Windows 7. Sorry, but it won't work on a mac or Linux.