175 years

Did you know? The safety pin as we all know it turned 175 years today!
Walter Hunt invented the safety pin and got U.S. patent #6281 exactly today, 175 years ago.
Safety pins are still in use for many things, although "velcro" replaced it partially.

Trivia:
Hunt made the invention in order to pay off a $15 debt to a friend. He sold the patent for $400 (now approximately 15,000 US dollars). The company he sold it too made millions with the patent.