lendle.me pay people to lend books

soapsuds

http://lendle.me/faq/
We pay all users a small credit for every book they loan through Lendle. The price we pay for each book varies based on the price, demand, and supply of that book. Our Patron members earn twice the going rate. Once you’ve loaned out a book, we wait the full 21 day loan period (7 days for the borrower to accept, and then 14 days for the loan) before crediting the lend. This is the only way we can ensure that lends are going through before applying credits to your account.

Once you reach $10 in credits, we pay out a $10 Amazon gift card. We pay out gift cards in bulk, twice a month.
参考
http://lendle.tumblr.com/post/5868644202/lending-guide
有电子书的可以考虑。