BGB is a GameBoy, GameBoy Color, and Super Gameboy emulator/debugger which runs on Windows. Program features accurate emulation of the hardware, powerful debugger, SGB multiplayer with up to 4 gamepads and TCP/IP game link support, graphics with GDI, DirectDraw, Direct3D, OpenGL output, and HQ2X, Scale2x, scanlines, blocky filter, accurate/high quality sound emulation, bandlimited synthesis, GameGenie and GameShark cheat, and more.

Here's changelog since v1.4.1:
1.4.2 - fixed a large number of small problems and bugs including: direct3d now works on secondary monitors, some accuracy fixes (including sagaia problem), added some features including: mono sound output and an exception break if making bad accesses during an OAM DMA transfer. tested to work on windows 8.

1.4.3 - fixed: loading/saving save files for roms with unicode filenames was broken if a save dir is not set. this was broken in 1.4.2.

Check out official website for further information and latest version of emulator.