you guys are gonna LOVE this project!
seems the eggheads over at Darpa are opening up the design process for the next generation of tracked vehicles.
http://vehicleforge.org/
We should forget about tracks altogether and think... 'Hovertank'.
Darpa offers 1 million dollar prize to design an amphibious tank
http://www.wired.com/dangerroom/2012/10/fang/