So, check out what this chap did with his PicAXE:
From http://tomthegeek.blogspot.com/2010/01/picaxe-08m-lego-tank.html
"Here's my first PicAxe 08M project, an IR controlled Lego tank. It features PWM Lego Power Function (LPF) motor control and a laser pointer "cannon". I built this because I wanted something fun to do with the PicAxe and Lego doesn't make any tank kits. This can be easily replicated using the LPF IR Remote and receiver but where's the fun in that? The turret rotates but only by hand, the 08M doesn't have enough pins to drive more than two motors. In the next version of the tank I plan on adding motorized turret rotation and elevation."
