Yves Saint Laurent bag, Besace, YSL

If we had to sum up the feel of 2008's fashion trends in just one bag, the Besace would be our obvious choice. YSL's newest creation defines everything that's now: laid-back, understated luxe.

Wear this one slung casually over a shoulder for a too-cool-for-school style. Only trained observers will be able to guess the price of your bag - the rest of the population will just think you're effortlessly chic. Jessica Alba and Jen Aniston are devotees.