This is a mod of all mods for the GameBoy Advance. Essentially converting it into a game console with an ability to attach a joystick, output video to a TV or an RGB monitor, and provide power management to get around wasting those batteries. The result is amazing and breathes new life into your GBA, even if you only decide to do the joystick mod. The controls feel absolutely different, and some games like Street Fighter Alpha 3 feel very similar to arcade using the four button Neo Geo Joystick controller. For horizontal shooters, the game pad will provide superior control. Contra Advance feels just like the SNES, in fact all games will now give you a feeling of playing on a console. What console would be complete without output to a TV or even better, an RGB monitor.
Although a complicated mod the GWGBA is described at the bottom of the page. Using the RGB mod and then connecting to the PSOne LCD monitor the picture quality is nothing short of amazing, no blurring, no dot-crawl, discoloration, or other side effects attributed to the low quality connection to TVs. Getting stereo sound from the 1Watt speakers on the monitor is also kewl. The picture kicks GBASP's butt all up and down the block. The power management mod allows your GBA to work without batteries like a true console, and with batteries when they're available. I also wanted to install the Afterburner but after trying the installation I found the image quality to be sub par, with washed up colors and some very visible lines on the screen. Now you're probably asking, what about just having a Game Cube, VGA cable, GBA Player, and a Hori Gamepad?
News source: Slashdot