Tank is ALPHA software, please see the README files. It may or may not work for you. Here you'll find some pictures, source code, binaries and other useful info.
Please see the release Notes. It still works better on a real OpenGL machine than on Mesa and it's slooowww on all non-accelerated platforms but if you feel courageous, follow the links. I've moved to other projects (XVfilemgr) so don't expect a new release until this summer, unless some kind people submit patches.