Whilst surfing Ebay one day I came across new RC monster trucks selling very cheaply. The interesting thing about them was that they had tank-style steering instead of the normal Ackerman steering like most RC trucks.
They can be bought in Europe from Seben racing and in the USA from Amazon and are called "Skull Crusher" from Toyabi.http://www.amazon.com/Remote-Control-Scale-Monster-Yellow/dp/B000ODT7RK
Here are some videos of the trucks in actionhttp://www.wilhelmy-it.de/seben/pictures/racing_king/king.htmlhttp://www.youtube.com/v/GFLU0xfkD3s&hl=en
I had a good robotty feeling about these asked my better half to get me one for my birthday.
The truck is HUGE and comes with a simple speed controller which is on/off rather than proportional, still, it was amazing what could be achieved with such a cheap model.
Stock, it will spin on the spot, climb all sorts of objects and gradients.
It has independent suspension and gearing to each wheel and runs from two small-ish motors. It is VERY big and came in an enormous box.
Construction is better than expected for such a cheap model, but the tyres are some kind of foammy PVC moulding. Apart from that, lots of space on board and has springs at each corner. The transmission is by gears down 4 articulated arms to the wheels.