Party on -- online

Two other potential gift card sources: blogs and social media. A number of bloggers regularly offer giveaways to attract readers. Do an Internet search with keywords such as "blogger gift card giveaway," and you'll find quite the lineup. Often, entering is as simple as leaving a comment.

Another hot search term: "blogger Twitter party." This is an online social event whose hosts frequently offer gift cards to encourage attendance. Find the events through hashtag searches on Facebook or Twitter, or through sites like Twitter Party Guide and Resourceful Mommy.

You must register in advance to be eligible for a prize, and other requirements may exist (e.g., posting a comment confirming your participation). Don't just show up five minutes before the party ends and expect to snare a gift card.

But do show up. Perales has won as much as $500 worth of gift cards in a single month.

"I did all my Christmas shopping with gift cards I got from the Twitter parties," she says.

Save those bottle caps

I know that soft drinks aren't good for me, but what's life without a little sin? Especially if you can make your habit pay. The My Coke Rewards program offers points for codes found inside bottle caps (three points) and multi-packs (10 to 25 points). My favorite prize is the free movie ticket, but you can also get gift cards for restaurants and retailers.

Or lodgings. A reader named Nancy W. has used My Coke Rewards points for hotel gift cards when relatives hit town. She has cashed in for gift cards to Panera, Red Lobster, Bath & Body Works, Olive Garden and Omaha Steaks, too.

"I really can use (the income supplement), even though I have a full-time job," says the Pennsylvania resident, who asked that her last name not be used.

My Coke Rewards generally experiences "a big spike" in card redemptions every autumn, according to spokeswoman Susan Stribling. "We assume it's people giving Christmas gifts."

I'm there myself, having cashed in points for gifts like magazine subscriptions, a set of barbecue tools, a movie-themed T-shirt and a NASCAR hat.

The old switcheroo

Drugstores want your business, so watch their ads: Some offer gift cards if you'll transfer your prescription or fill a new one. Before I got into an HMO with its own pharmacy, I took pains to buy prescriptions from places that would pay me back. I also transferred prescriptions from place to place whenever possible.

Sometimes these programs are limited to first-time customers. But a pharmacy may define that as "someone who hasn't filled a prescription for six months." Read the fine print.

Note: If you take more than one medication, say so. Pharmacists need to be on the lookout for possible drug interactions.

If a coupon is required, clip it and put it in your wallet; that way, you're prepared for when someone in your family needs a prescription filled. Write the phone number of the most conveniently located pharmacy on the coupon, so you can get the doctor to phone it in.

The prize for the oddest drugstore promotion: a $5 CVS gift card for turning in expired or unused prescriptions, reported by a Florida reader.

Tips from the pros

The question is whether you have the time to answer surveys, click on emails or attend Twitter parties. Only you can answer that.

How much of your life you can devote depends on the kind of life you have. An at-home parent can answer surveys while watching the kids play in the yard. A light-rail commuter can click on emails via her smartphone.

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Learn to work those gift-card giveaways with advice from those already who do:

  • Spam happens. Start a separate email account. You'll also probably get newsletters, updates or bonus-offer emails.
  • Branch out. Look beyond surveys and searches. "How MyPoints Works" explains all point-earning tasks. At the bottom of the Swagbucks home page is a "Ways to Earn" section; an independent online guide called Swagging 101 is a big help, too.
  • Hint, hint. Check the Swagbucks Facebook page from time to time, and watch for "thanks for the code!" messages from members. When you see one, start looking for a "Swag Code."
  • Workplace points. In charge of ordering office supplies for the office? See if what you need is available through a rewards site.
  • Down and dirty. If you're not squeamish, check the lunchroom recycle bin for Coke products. I look for caps everywhere, and I find them. Lots of them.
  • Be patient. Points do add up. In time you will have enough to buy something for someone else or for yourself -- especially if you get chosen for a 10,000-point survey. I wish.

Donna Freedman is a freelance writer in Seattle. You can find more of her writing on MSN Money's Frugal Cool blog and at Surviving and Thriving (motto: "Life is short. But it's also wide.").