While at work today I saw a guy that I work with had 3 books on the stock market in his cube. I asked him if he had read them, and when he said that he had I asked him how they were. He said they were alright but he couldn't ever get out of debt enough to have money to put into the stock market, so they were pretty much a waste for him. I asked him if I could read them and he GAVE them to me. He told me to take them home, he didn't want them anymore! I could have gone to the library and did the same thing, but I own these books now! All because I asked a question and have a 5 minute conversation. It was worth it!
Also recently I've been on this kick about signing up for free samples. There are MANY websites out there to find free sample on, and while most of these are marketing schemes to get you to buy more of their products, you're ultimately in control of what you buy and you're getting free stuff! I like getting free stuff, and normally it isn't stuff I'd spend my money on anyways, but every now and then you can try free laundry detergent or free shampoo or body wash which just saves you money from not having to buy more of your "regular" when you can use the free stuff.
I may find that I regret giving my address out to all these companies, but it is easy to just throw things away. I don't let junk mail bother me, it isn't worth it!