At some point I'll add some information about this project. In short I'm using a PIC16F873 microcontroller, MPXA4115 pressure sensor, MMA2202 accelerometer, and FM24256-S FRAM memory as the core hardware. The software will take in data from the various sensors, do some magic, store this data in FRAM, and beep out max altitude and make the entire flight log available via RS232 through a MAX233 chip. Here are some random pictures at various stages of progress:

Plot of raw data from a 10 bit ADC, no hardware filtering

Plot of 64 sample averages, hardware filtering and decoupling. Left image has the Y axis auto scaling, right image is to the same scale as the above picture.