I’m a fan of Mars rovers and some family members just built me one from Legos:

This is a model of the Mars Exploration Rover (MER), two of which are trundling around up on Mars. (Well actually one is done rolling but the other, named Opportunity, is still exploring.)

And here are life size models of all three rovers, Pathfinder, MER and MSL (on its way to Mars now), as seen at the Jet Propulsion Lab: