Today's tip is part of our Fiscal Fitness '09 series. Every weekday this month, you'll get help getting fiscally fit as we work toward our goal of saving $2,000 to invest in 3 stocks!

Stop picking the spinach from your teeth with that unredeemed gift card and using that old MP3 player as a paperweight. There's cash to be had for your cast-offs -- even if it's just $40 for an early-generation iPhone or 70% of the value for the remaining balance on a gift card.

There is a market for everything and a place to hawk it to the highest bidder. Here's a brief rundown of services to use to turn your trash into cash.

Old electronics and other gadgets: Most of us have a veritable gadget graveyard somewhere in our home. (Attention Smithsonian curators: I recently unearthed a stack of five-inch floppy discs at the bottom of a closet.) Clear up some drawer space and get some cash. Gazelle.com (which buys cell phones, digital cameras, camcorders, portable hard drives and more) says that on average, it pays its customers $115 for their unwanted electronic doodads. Recently, a Blackberry Pearl 8110 fetched $90 and the 8830 World Edition was worth $29 to $36. Another spot to check is BuyMyTronics.com, which will buy some cell phones (definitely iPhones), PDAs, and game consoles. Payment comes via Paypal, a check, or a Visa gift card once these services verify the condition and market value of your items.

Even retailers have gotten into the trade-in business. GameStop (NYSE:GME) relies on used video games and game systems for a significant part of its business, while RadioShack (NYSE:RSH) and Costco (NASDAQ:COST) have trade-in/recycling programs for everything from old computers to unwanted GPSs. But instead of cash, you'll typically get store credit for your cast-offs.

Gift cards: You might think they're duds, but gift cards can be worth, well, almost their face value to other folks. With billions of dollars of gift card balances going unredeemed every year, it's no wonder there's a crop of services to help consumers off-load them. You can auction it off (Cardavenue.com), sell it outright (Giftcardbuyback.com), or swap it (Swapagift.com) for something better. You'll typically find a full menu of cards online from stores like Lowe's (NYSE:LOW), Wal-Mart (NYSE:WMT), and Cheesecake Factory (NASDAQ:CAKE), among dozens of others.

Don't expect to get full face value: Most pay out anywhere from 60% to 90% of face value. (You'll get top dollar by selling cards of hot retailers, in round dollar amounts, and with long (or no) expiration dates.)

Some sites charge you a percentage of the final transaction, and others charge a flat fee. Balances must typically be at least $10 to be eligible for swapping, trading, or selling. With the average recipient's gift card balance at $52, getting 60% to 90% of the face value gets you $31.20 to $46.80 of actual cash you can blow anywhere you want to.

Unused airline miles or points: At Points.com you can swap, share, or redeem your unused rewards. If your points are spread around, you can even combine them so you can get something -- a gift certificate, song downloads, etc. -- before your points expire. Another option is to donate your miles to a cause. Many organizations are set up to facilitate this transaction directly.

Oddball, unusual, and limited-appeal stuff: To get top dollar for your collectibles and other items that might not have mass appeal, eBay (NASDAQ:EBAY) is still the obvious first choice. You don't even need to go through the hassle of setting yourself up as a merchant. Simple take the treasures from your attic to an eBay drop-off location, and they'll conduct the transaction from start to finish for you. For a fee, of course. At the other end of the spectrum is craigslist.com, a digital town crier where you can list, for free, the stuff you want to sell.

Clean out the attic this weekend
There are plenty of other places to sell your unwanted stuff. Consider the following:

  • Consignment shops are great for designer-label clothing that's in good condition.
  • Jewelry stores or pawn shops for that gold rope chain you sported in the '80s which can be sold for its value in scrap.
  • Children's consignment shops are a popular way to get at a little money for those toys, clothes, and strollers that your little one has outgrown.

More ways to save ...

  • Dump your land line and save $33 a month. SmartMoney.com, citing a recent Nielsen survey, makes the case for giving up your land line phone service entirely. According to the study, households that only had wireless service used just 332 more cell phone minutes per month than those that also had a land line. Even with the added chatting minutes, wireless-only customers spend $33 less per month on phone service.
  • Host a party. If you're gearing up to clean out your closet or the basement, why not have a swap party? Invite over friends, and friends of friends -- as long as they bring items to swap. Then swap away! Everyone will walk away with something "new" without whipping out the wallet.

Read the latest from Fiscal Fitness '09: 1 Month, 2 Grand, 3 Stocks to get our other money-saving tips. You can also keep up with our tips through our daily Foolwatch email. Share your frugal insights and experiences through our Fiscal Fitness '09 discussion board, or leave a comment below.

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Fiscal Fitness boot camp instructor Dayana Yochim owns none of the companies mentioned in this article. Wal-Mart, eBay, and Costco are Motley Fool Inside Value recommendations. GameStop, eBay, and Costco are Motley Fool Stock Advisor recommendations. Try any of our Foolish newsletters today, free for 30 days. The Fool has a disclosure policy.