Want freebies? Drink some soda

Diet Coke is my caffeine of choice. I see no reason to pay retail, though, so I use the My Coke Rewards program. Although I could cash in for premiums as varied as garden tools, an MP3 player and a retro toaster, I tend to focus on vouchers for free 12-packs.

Here's how a frugalist does it:

• Collect points, mostly from other sources (more on that later).
• Trade them in for a "free 12-pack" voucher (two of them, if I have enough points).
• Watch for a "buy two 12-packs, get three free" sale.
• Cash in, and drink up.

In other words, I pay for one (or none) of the 12-packs and wind up with five, which can last me a couple of months. Since each box has a 10-point code, it means an additional 50 points toward my next 12-pack.

Yes, I know sodas aren't great for me. (Boy, do I know it: My sister is a dental hygienist.) But what's life without a little sin? Especially if you brush your teeth afterward? (Post continues after video.)

Each bottle cap from a Coca-Cola product -- including Powerade, Nestea, Minute Maid bottled juices and some varieties of Dasani water -- has a code worth three points. Multipacks bear codes worth 10 to 25 points.

Since a 12-pack voucher costs 250 points, that could mean a lot of soda drinking. But I've got a frugal hack for that, too.

No lids? No problem!
Friends, relatives and an employee at my favorite teriyaki joint save codes for me. I'm a cheerful scavenger who picks up caps and boxes when she sees them, either on the ground or in the trash.

I'm more of a Dumpster wader than a Dumpster diver. But if a 12- or 24-pack is within reach I'll get it, remove the code and put the rest of the box in the recycle bin where it belongs.

• Bing:The most popular soda in the U.S.

My most reliable source, though, is a nearby university. Its library recycle bins bristle with empties, and campus trash cans have separate sections for bottles and cans. When a soda or juice bottle is visible, I remove the tops.

Hey, it's stenciled right there on the bins: "No lids." By scavenging the caps, I'm actually doing a good deed.

Maybe you're thinking, "Take a box out of the trash? Pick a soda cap up off the sidewalk? Disgusting!"

Then don't do it. Leave them for us scavengers. Over the years I've heard from other My Coke Rewards fans, including the lucky stiffs who get not only points for the cap but 5-cent deposits for returning the bottles. (I wish.)

Is it worth it?
Six years ago, when I was really broke, I redeemed single movie ticket/soda combos and put them in my daughter's Christmas stocking. The deal cost fewer points back then; as I recall, it I was 330, compared with 485 points now.

These days I regularly send codes to her and my son-in-law. (You can have one account per person, and as many as five per household.) Their preferred premium is the pair of AMC movie tickets, plus two sodas and a large popcorn. Since that costs 1,100 points, they're glad to accept my extras.

You're allowed to enter up to 120 points per week. Thus, in about a month you can get a single ticket and drink -- frugal fun when money is tight. (For another option, see "Go to the movies for free.")

Obviously, this tactic isn't for everyone. But when tickets cost $10 or more, it starts to sound more worthwhile.

One more tip: Give the recycling bin a tap before reaching in. Otherwise you might be unpleasantly surprised by a wasp attracted to the sweet smell of Vanilla Coke.

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