Here's the skinny on skivvies

What's the first thing you put on in the morning and the last thing on your mind?

WHY, underwear, of course.

And, yes, it's a cause for celebration.

Thanks to the skivvy retailer Freshpair.com, today has been anointed National Underwear Day. In light of this most glorious, dubious holiday, we thought we'd share some fun facts of the undie variety, brought to us in part by the fine folks at Freshpair. And don't worry -- we'll keep it brief.

• In 1991, the average American woman's bra size was 34B; today, it's 36C. Chances are the findings don't apply in Hollywood.

• Married men change their underwear twice as often as single men. Darn right they do.

• It's widely believed that the concept of the chastity belt is a myth. Rather than a device imposed on women during the Crusades, it was largely a poetic metaphor that became a romantic novelty in 19th century England. Sales at Ye Olde Chastity Belt Shoppe have not recovered.

• There is a line of men's underwear that boasts a pocket especially for an iPod.

• Four percent of men prefer thongs. One hundred percent of women in their right minds prefer men who don't prefer thongs.

• The first bra was engineered in 1913 by New York socialite Mary Phelps Jacob when she tied handkerchiefs together with a ribbon. The bra strap snap was invented by a 12-year-old boy.

• Both Louisiana and Virginia have unsuccessfully attempted to pass laws that make it a crime to sag your pants below your underwear. California passed a rebuttal law requesting that they not hate the playa'.