VisualBoyAdvance is an emulator for Nintendo's Gameboy Advance. It also
supports emulation of the Gameboy (classic), Gameboy Pocket, Gameboy Color
and Gameboy Advance SP.
Some of the main features are:

- option to use BIOS file
- zip/gzip file support
- graphic filters Normal, TV Mode, 2xSaI, Super 2xSaI and more
- interframe blending support
- built-in ARM/THUMB assembly debugger
- 10 save states accesible through keyboard
- automatic battery file load/save
- auto-fire support
- 16, 24 and 32 bit desktop support
- GDB remote debugging (see below for information)
- AGBPrint support for development
- RTC support

WWW: http://vba.ngemu.com/