Despite what P. Diddy may say, the treasury just gave an upgrade to the lowly five dollar bill.  Check out this delightful summary of the changes, including the massive purple five on the back.  This has been a public service announcement.

p.s. For all the numismatists out there, or if you just want a blast from the past, check out the 5 dollar bills from 1886,  1896, 1907, and 1923, courtesy of Wikipedia.