Part of me almost hates to publicize this, as I like to see business going to bookstores. But on the other hand, it’s hard not to acknowledge a good idea when you see it, and this is definitely one.

The San Francisco Chronicle yesterday profiled two websites that create online book swap communities. Both BookMooch.com and PaperBackSwap.com are set up to allow readers to trade books they’ve already read.

They operate very similarly. Basically, you list the books you’re willing to part with and then search out others that you’d like to acquire. Where you can make a trade, you do. The only cost to you is postage.

“We believe in saving money,” PaperBackSwap founder Richard Pickering told the Chronicle. “We also believe in recycling.”

In addition, it’s a nice way to create an online book-loving community. Websites like these can never replace the joys of an evening spent browsing in a bookstore (surely one of life’s great pleasures) but they clearly have their advantages.

O Magazine calls the concept a “stroke of genius.” It’s hard not to agree.