The Fifth Pocket

The answer to this one is easy -- coins. It has to be coins, right? We scoured dozens of online jeans listings. Pretty much every "classic five pocket design" boasted a coin pocket in the front right scoop pocket. Some of the coin pockets were exposed, some had flaps, some had insignias, but they were all described as coin pockets.

But then we stumbled onto a similar query on Ask MetaFilter and found the real answer -- watches. Back in the day before the wrist became multi-functional, folks carried pocket watches. These were fastened to the end of chains, and stored in special pockets woven into pants or vests.

Levi's 501s, originally introduced in 1890, featured watch pockets. And sure enough, after more snooping around, we found these vintage jeans from the 1970s listed as having "five pocket styling with watch pocket."

Taken from Ask Yahoo