The Book Rack is a great way to find inexpensive used books that you'd like to read. They will also swap the books you bring in for ones that you want. I used to go there all the time when they were having a bring two in get one back deal. I know that they used to calculate up the money you'd get for the books and that would be your Credit to spend at the store too.
All in all its a great find for inexpensive books, sort of a Half.com brick and mortar store.
PROS: cheap and easy
CONS: selections will always vary on customers
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