Visual Boy Advance Game Boy Advance Emulator for Linux/Unix
Version 1.7.1
An awesome cross-platform GBA emulator.
Visual Boy Advance Game Boy Advance Emulator for Mac
Version 1.7.4
This is a very nice port from the PC version that features great ROM compatibility.
Visual Boy Advance Game Boy Advance Emulator for Windows
Version 1.8.0 Beta 3
This is the best free Gameboy Advance emulator ever.