if your in college and go to either a CSU or UC then i have just the thing for you!
check out ULOOP.com
its basically like a craigslist, but specific to your college campus. i know that ive already seen a bunch of cool stuff up for sale, and even some skiing stuff! but i got all my books through it this year, and it saved me like 200 bucks. just go check it out, all you need is a school email address and its totally free!