ideas are cheap. what next?

Worst case, take a long weekend, en come over to the House Of Chaos. Not the first roboteer taking a stop here, and have a lot of building fun.

:D wow, that's a very generous offer, and one I will most certainly take you up-on at some point. I will trade you bacon knowledge for bot-building knowledge, how does that sound?

Me Hungry.

If you look around you can often get power drills cheaply or for free. This is because the battery pack is usually the first thing to go and it is hard to get replacement ones so people buy new drills. People on this forum will be glad to tell you how to get the chucks off them and extract the motor and gearbox. Buy a pair of red wheels and you have the motive power for your robot.