on this year's winning NASA Lunar excavation robot, there were these tracks.
Thy consisted of aluminum C-stock fastened to chain that had special links that allowed things to be attached to them without modifying the sprockets. you can find them here:
http://www.mcmaster.com/#roller-chain/=6s0umt Scroll down to the bottom and click on accessories. Unfortunately, they're only available for 35 pitch chain.
EDIT: Here's a pic of the link.
