Anyone else want one of these?

[Lizooki]

Lennox mini-crawler. The smallest tracked vehicle ever produced and yes ..... made by the Lennox A/C people.
With a 6 hp lawn mower engine, it won't push a lot at one time ..... but you could give the sandbox absolute heck!

 

[Lurch830]

Check out the Steiner mini-tractors...all the connections of a standard tractor, but it will fit into the bed of a pick-up & they're 4WD!

They're articulated which could take some getting used to, and the one I used had all the controls on your right hand which got interesting.