I just came across OpenXC, which is an open source Android and Arduino based API for cars that interfaces with the car via OBD. I'm not a software coder but I'm sure that there is somebody on ClubWRX who would find this interesting/useful. I don't know much about what data is captured by the ECU on a WRX but perhaps you could create a datalogger that connects to your Android device via USB or bluetooth. You may even be able to modify the ROM using OpenXC if you knew what you were doing.
Anyway, I thought OpenXC sounded interesting and figured I'd share it here in case somebody else might find it useful.
The website is http://www.openxcplatform.com