We all have books gathering dust on our shelves or movies that we bought and know we'll never watch again. So next time you spot a book or DVD you'd like to buy, why not save your money and make a trade instead? There are a handful of sites that let you do this online, with Book Mooch (www.bookmooch.com) and Swaptree (www.swaptree.com) among the most popular. How much can you save? According to one of Swaptree's founders, Mark Hexamer, the site's users get about $30,000 worth of free media every day by trading up—that's almost a quarter million a week. With most sites, you cover the cost of shipping, but the media mail option at the post office means you're only looking at a couple bucks.
A similar concept that caught my eye as a mom is Zwaggle.com. Parents know how fast babies and toddlers outgrow clothes and shoes, and keeping up can put a major dent in your pocket. With this site, you can trade the items your child no longer wears or uses for the things you need—including strollers, high chairs and winter coats. Again, you pay shipping, which Zwaggle spokesperson Caitlin Haedicke says usually averages around $7.