Other uses for Ardupilot 2.8?


I have a large Quadcopter I built up and running for some time now, and left over from the build, is a spare Ardupilot v2.8 which I wonder whether I might use for a simple Arduino type project… I am fairly familiar with the Ardupilot boards, however am new to arduino, and so, I wonder how closely they are related in design and funcion?
I would like to repurpose the Ardupilot to control a solar tracking system for an experimental energy project in my back yard, is this possible?

Also, I have picked up a Digispark Kickstarter Attiny85 board, which I am hoping I might program using the Ardupilot board… is this a possibility?

Here’s hoping for any useful info out there comes my way, as it would save me a few quid and I can move along that path