Here is an small terrain piece I worked on for the 3" Base Competition over at TerraGenesis. As the title of the competition suggests, the base is 3" on each side. The tin is from a pop can and was all corrugated with a paper crimper. Before corrugation, however, I sanded it with an orbital sander to make some holes worn through. The armature of the tree is twisted wire covered partially in Sculpey and sawdust/glue. I'll do a proper tree tutorial sometime in the future, but I need to give credit to 'grove den' and his great tree making thread. The foliage for the tree is similar to that of making bushes - just apply the static grass to the small tree branches rather than the steel wool.
Eureka Miniatures. They are based in Australia and they have a US distributor as well. I sculpted the tires from Sculpey.
The competition was tough, but this project came out in 1st place. I also have an entry in the Defensible Position Competition featuring a lot of the recent details that I've posted recently. The competition ends soon so if you like it, please feel free to visit the site and vote for it! Even if you don't vote, you should definitely check out the other great terrain related material on TerraGenesis.