It would be interesting if someone could write a plate tectonics simulation program that ran backwards in time. The "initial condition" would be the Earth's current state. The program would then show the state as a function of time of Gondwana and Pangea including mountain ranges, rift zones, rivers, etc. It's interesting to think that there must have been numerous alpine vallies as beautiful as Yosemite and Interlaken that no human being ever saw. That rift zone between Southern Australia and Antartica would have put the Grand Canyon to shame.

It's too bad that interstellar travel isn't feasible. It'd be cool to tour the inhabitable world's of the galaxy, check out the local scenary and rub elbows with the natives. I'm an incurable tourist and the Earth is too small.

Gary