I'm curious if anyone here has tried any of the online book swapping services? If you're not familiar with it the idea is that for a small fee you receive a copy of a book from another trader in the group and you offer up your own books for trade. Some sites seem to offer incentives if share your own books.
Since I still read and purchase a lot of paper back fiction this seems like a great way to get copies of books off my shelf and into the hands of another reader. Likewise I'd be able to get books cheaper than from a book store.
Does anyone have experience with any of these groups?
The popular ones (from my quick googling) seem to be:
http://www.bookins.com
http://www.frugalreader.com
http://www.titletrader.com
Thanks and take care.
-Jason