Amazon is currently giving free 1 year memberships to Amazon Prime (free 2 day shipping, $3.99 overnight shipping) to current students with a .edu email address:
http://www.amazon.com/gp/student/signup/info I'm not sure how long they're offering this (it doesn't say on the site).
Just thought i'd give fellow sociology students the heads up on this in case you haven't heard about it yet. This is going to save me a ton on shipping textbooks this year!