How do you play gba games online

Go to http://www.vizzed.com/playonlinegames/index.php?system=gba&ref=108749 to play every GBA game ever made, online, completely free! Only thing is, you need to register on the site in order to save your games, and, you need to download a plugin (takes like 30 seconds). Unfortunately, the site does not currently support Mac, but you can play on any version of Windows XP and up.