Black denim, thrashed within an inch of its life, is hot for fall. And, judging by Martin Margiela's Spring 2009 collection, will continue to be hot through that season, too. So what's a girl on a budget to do?

If you're not willing to shell out major bucks for a pair of designer jeans that look like they've been through a garbage disposal, no worries. There's always the DIY option, which only costs as much as a pair of scissors and a cheap-o pair of denim. (Or better yet, a free pair from your closet.) Punk rockers have been doing it for decades.

But, if you'd rather go the lazier route (like us), there are plenty of wallet-friendly cousins to the runway counterpart. Here are our favorite roughed-up black jeans under $100: