Remember fanny packs? Those useful little pouches tourists and body builders would sling around their waist? Well meet their new, updated and suuuuper fashionable counterpart, the arm purse.  As modeled by the lovely Agyness Deyn outside of the Chanel store launch party in London this evening, this little elastic banded number has all the convenience of a normal purse, but with out the cumbersome shoulder strap.  You'll never forget this accessory!  Arm purses, they're carrying us into the future!