Don't You Wish You Could Travel To The Future!

Travelling into the future is easy. We're all doing it, at a rate of one second per second. So the question is really just a tricky way of asking "What coins do I want to have in a few year's time when I'm older?".

Speeding the rate up is relatively easy, too, and I mean "relatively" in both senses of the word: simply travel at close to the speed of light, and relativity will take you into the future at a much faster rate than the rest of the universe. Unfortunately, current technology doesn't allow us to travel at anywhere near that kind of speed.

Another option is the "Buck Rogers method" of time travel: freezing yourself. Of course, you'd have to make sure somebody doesn't come along and steal your stash of coins while you're cryosleeping.

But travelling back to the present again once you make the trip, that's the really tricky part. Because you'd be in the future, and travelling back to the present would be going backwards in time - something, as has been pointed out in the other time-travelling threads, which is either completely impossible or only possible with the aid of extremely hyperadvanced technology, and a universe which didn't disallow such things from happening.