5 ways social networking sites save money

Peer-to-peer lending websites such as Prosper and Lending Club match lenders with borrowers. The result: Borrowers save money on interest rates by cutting out the middleman -- banks. These websites have created a booming sector that's slated to climb by 800 percent this year to $5.8 billion in loans, according to research firm Celent. The loans are primarily personal, auto and home-improvement loans.

For example, Lending Club borrowers pay 7.93 percent to 25 percent in interest, depending on their credit history. "Our rates are 20 percent to 30 percent better than banks," says Rob Garcia, senior director of product strategy at Lending Club. "And you can get funded in a few days."

But you need good credit scores. Lending Club looks for FICO scores of 660 or better. At Prosper, it's 640. Both sites tack on extra fees. At Lending Club, you'll shell out 2.25 percent to 4.75 percent of the loan in origination fees. At Prosper, closing fees run from 0.25 percent to 3 percent.