Osmose is a Sega Master System / Gamegear console emulator. The emulator is
released as open source project, under GPL license and exists for both Linux and windows.

Note : Due to the major change in the renderer, this version is a Beta so, if you try this version, please let me know how it works for you.

Features:

-SMS emulation: Good compatibility. At this stage, the emulator can run* 96% of commercial
games and public demos, except games that relies on codemaster mapper, which work
but does not have proper video mode emulated.
-Game Gear emulation : Good compatibility. At this stage, the emulator can run 98.0% of
game gear ROMS.
-SN76489 Sound is supported, but still needs work.
-support. for .ZIP .SMS and .GG format.
-Video filters: monochrom, scanline, scale2x, bilinear, nearest neighbour, scale2xscanline (fullscreen option always available).
-Pad(keyboard or joystick mapped), Sport Paddle (mouse mapped) emulation.
-PAL/NTSC Timing.
-Japanese/Export console.
-In game Screenshots, GFX rip, sound shot.
-Accurate auto-frameskip.
-Configurable keyboard configuration.
-Joystick support.

What's new in Osmose 0-8-5b:

-Osmose now uses OPENGL for render for a serious speedup (120fps for 11%cpu load in fullscreen on my old development machine). Bilinear filtering cost almost nothing now, whatever is osmose window size.
Note that it's now possible to resize the window.
-Only Bilinear and Nearest Neighbourfilters remain.
-Use a lookup table instead of switch / if else for TextWriter (Faster).
-FPS is now writen into emulated display instead of Window's Title so it can
be seen in fullscreen.
-Emulator is less verbose now. It does not say what it doesn't do anymore :)
Few changes in emulation statistics presentation.
-ZLIB is now installed by default on most linux distribution so Osmose does not
keep zlib source code into it's source tree, and uses the libz shared object.

Here are few screenshots: