You could use a normal wheelbarrow to transport various materials while working outside, but that doesn't involve anything mechanical. No fun! What about this insane Honda HP450 Power Carrier? It'll put any other wheelbarrow on earth to shame.
The Power Carrier is driven by a pull-start 163cc, 5.5hp 3-stroke engine, allowing it to carry up to 992 pounds on steady ground, which is far more than your puny arms and a traditional wheelbarrow can tote around. And hey, once you drop off your load you can hop in and use it to ride back to where you need to go.