I use class notes (we have good note packs for each block) instead of books. I buy pretty much everything from Amazon though... including non perishable groceries (if they're cheaper than walmart, whnich they almost always are). You can find some badass brands that stores don't even carry. Plus, there are reviews if you're skeptical about anything. Yesterday I bought some awesome pancake syrup that's not even carried in stores!
And, in case you bought the wrong item, or you realize you don't want it anymore, you stick back in the box, print out a FREE shipping label from Amazon, and return it to them. I just give the box to my rental office on my way to my car!
Beats going to the store and you save a crap load of money. AND I need to walk up the stairs to my apartment, so they eliminate the hassle of having to do that since my mail is delivered upstairs! Now only if I can get them to start selling bottled water. That would be my equivalent of winning the lottery actually.