GBA Game Development Competition
SimonB writes "gbadev.org is hosting its yearly game development competition (for the GameBoy Advance), with a deadline in just under a month from now. What is different (and exciting!) about this competition is the fact that the winning entries will be made into a multi-game compilation and 500 cartridges will be manufactured complete with cartridge label, full color box, and manual. The finalized game will be sold to break-even and the aim is for the game to cost just under $14US with shipping included. Visit 2004mbit.gbadev.org for more information."
http://www.lik-sang.com/info.php?category=51&produ cts_id=1415&
Lik-sang has something that can do that. But it's only for small apps (256 KB or less).
http://www.linker4u.com/pp/linker4u.asp
This site though has some Flash based cartridges you could probably use to upload homebrew ROMs onto it.
I got mine from www.jandaman.com They have several different sizes and brands to choose from