Famous quotes that have the same meaning as "Let me cross that bridge when I come to it.." ?

Umm, that's not QUITE what that quote means. It's not meant to suggest that you should do whatever you want, without regret. It's meant to suggest that you shouldn't worry about things that MAY happen, but that aren't actually problems right now. It's a bit like "don't count your chickens before they hatch", except that that one is suggesting that you not get your hopes up, whereas this one is closer to suggesting that you not get worked up about problems that don't exist yet. It's also a little bit like "putting the cart before the horse", which means doing something in the wrong order. But if what you're looking for actually is expressions that mean "do whatever you want without regrets", then you could say "make hay while the sun shines", or "when the cat's away, the mice will play". Damn the torpedoes, full speed ahead.