it's an nice tank. but mine is better!
however your caterpillar is better.
how does it come that it doesn't pull apart? larger hinges or, what!
http://www.algodoo.com/algobox/details.php?id=40978
It works with a realistic weight as well. When you manage to make the turret controllable it would be even better. And if you could make it shoot you might just might have created one of the best vehicles in Phun.
10/10 for the fact that it is super reliable and looks the way it looks.