Post Office motto? Well, not the one you're thinking. That's actually what Herodotus says of the Persian post system. It's actually really cool, and might put you Americana folks in mind of the Pony Express.
See, the kings had had outposts built at precise intervals along major thoroughfares. At these outposts waited fresh horses and riders. Whenever messages or mail was sent, these riders set out as quickly as they could to the next outpost. Handed off their message to the next guy, etc.
The result? "There is nothing mortal faster than the system the Persians have devised for sending messages," says Herodotus.
This comes up at the end of the war. When Xerxes burned Athens, he sent a message of his victory. The folks at home in Susa were so overcome with joy that they strewed myrtle in the streets, burnt perfume, held feasts, and pretty much declared it a holiday. Then, well, just a few days later came the news of defeat at Salamis. Joy turned to mourning, clothes were ripped and weeping and moaning could be heard in the streets. They were especially worried about Xerxes--apparently the news didn't include how he fared, and the people were terrified something had happened to their king.
Goes to show how loved he was, eh?
Anyway. I love that this system of theirs is so renowned for its efficiency that it has influenced our own postal system. Just goes to show ya that it doesn't have to be digital to have virtual wings.