Tyler Clites has built the space marine light assault vehicles (SMLAV) inspired by the Warthog from Halo. By popular demand, Tyler created a set of quality instructions available for purchase at a very reasonable price of $5. Having built the SMLAV from his instructions, I can say that parts for the model are easy to acquire and the model itself is very solid.
Check out these fun variations of the SMLAV and military variants.