I was originally thinking along the lines of hillclimbing jeeps. But imagine a treaded vehicle that could automatically level and pave a road. There are these things https://www.youtube.com/watch?v=jkVBg_-OviI and these things https://www.youtube.com/watch?v=3ZMPoHahaj8 but they all look like they're running on ground that has already been cleared and leveled. It would be really interesting to see something that could dig through ground and rock like a tunnel digging machine and compresses the material into tile blocks to use as pavers.