Twenty Years ago Space Invaders ruled the video game world. It is easy to see why the formula worked so well: you are heavily armed and heavily outnumbered by the enemy. It is the same basic model that works so well for everything from 1942 to Mario to StarCraft to Halo. Peril is increased by the enemies moving faster and faster the more of them that you killed.

With this JavaScript version of Space Invaders you can relive the classic battles without having to download anything but a web page. The game uses the YUI and demonstrates how far JavaScript has come from the days of simple form validation and button mouseovers.