Bring it on. I'm sorry, but there is no reason for anyone to ever set foot in a post office. None whatsoever. You can print stamps on your computer. You can even get them from the ATM when you stop to get cash. And if you happen to be mailing anything other than a first class letter (which, by the way, is illegal for any entity other than the federal government to deliver), you're better off going with UPS or FedEx.
It's time this government-created monopoly was forced into the competitive free market. Where's Lysander Spooner when you need him?