Write GameBoy software with the SGADE

If you ever wanted to play around with writing software on your old GameBoy that you never use there's a project called SGADE (The Socrates Gameboy Advance Development Engine), available from here:

http://www.suddenpresence.com/sgade/index.htm

Additionally, I just found that if you want to watch DVDs on your GameBoy it's all possible, and more, with this amazing GBA Movie Player cartridge from Lik-Sang:

http://www.lik-sang.com/info.php?category=6&products_id=3983&

Here's a site all about GBA movies:

http://www.gbafilm.com