I've been looking at various computers used on rocketry and they don't provide the flexibility of adding other sensors or extra functions to their products, also, their costly, 400+, and they need a HAM license, which I don't have.

So my first thought was: you guessed it! Arduino! But come on, I can do better than that. Why not plain old AVR programming? I have the extra 2kb that the Arduino boot-loader takes away, plus it's easier to manufacture a board this way.

Im thinking on using the "Sensor Stick" that was featured on HaD's main page on May 4. It has 3 of the most common sensors  I'm going to use: Accelerometer, Gyro and pressure; plus an added one, which I was thinking on adding Humidity, since in theory we know the humidity of upper atmosphere but we haven't been up there or have we?