Not all input devices are created equal. Some of us long for that old coin-op console joystick every time we bring up GalagaREMIX on the iPhone, while others can't imagine engaging in a first person shooter without the aid of his or her trusty mouse. To that end, PSP hacker
TokyoDrift (not his / her real name) has wired an old PS2 mouse into his portable's serial port, by way of an ATMEL ATmega8 chip-sporting breadboard. The various PSP buttons can be mapped to the mouse's buttons or scroll wheel, and scaling and sample rates are adjustable. We know there are plenty of you out there that can't wait to try this one out for yourself -- so hit the read link, peruse the forums, and get inspired.