You may have some money you don't know about, hidden in grocery store loyalty programs and frequent flier accounts.

And with the holiday shopping season upon us, wouldn't it be nice to pick up some gifts without spending cash out of pocket?

From time to time, and this is one of them, businesses with loyalty programs roll out some great deals that allow people to acquire gift cards and merchandise.

You may have some airline miles that are about to expire, or grocery store points that have gone unused, that are more valuable than you realized.

Here are several of my favorite examples of current reward program offers:

Piggly Wiggly has brought back its "Greenbax get you gift cards" promotion, which allows the grocer's customers to cash in loyalty-program Greenbax points for gift cards in various denominations.

Greenbax are credited to shoppers accounts when they buy groceries, and for people who took advantage of the store's previous promotion, in which one Greenbax was awarded for every grocery coupon redeemed, Greenbax can turn into lots of free gift cards.

The gift cards are available at Piggly Wiggly stores. For 15 Greenbax, you can get a $15 gift card for a variety of retail stores. It's a good deal, but only half as good as it was in 2010, when 7.5 Greenbax would get you a $15 gift card.

Last year, I mentioned in this column that Southwest Airlines was running a promotion in which people who signed up for the airline's affiliated credit card received two round-trip flights.

If you signed up for Southwest's credit card then, or really at any time, check out their current promotion in which Southwest Rapid Rewards points can be cashed out for gift cards at a reduced rate.

If you aren't planning to use Rapid Rewards points for a flight, or don't have enough points for a flight, then using 4,000 points to get a $50 gift card is a pretty good deal (though only available to those with a Southwest credit card). That works out to 80 points per $1 of gift card.

Rewards points are redeemed for airline travel at a rate of 60 to 120 points for every $1 of airfare, depending on the class of flight, so the rate for gift cards is unusually good.

Harris Teeter is running a promotion that allows shoppers enrolled in the grocery chain's VIC card loyalty program to buy a $25 gas card for $20, every time they spend $40 on a shopping trip.

The promotion has been going on for months, so if you shop at Harris Teeter with a VIC card and you weren't aware of this deal, you may be eligible to buy lots of discounted gas cards.

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Use them yourself or give them as gifts: It's like buying gas for 20 percent off, or roughly $2.54 a gallon of regular unleaded based on the average price in Charleston last week.

The deadline for the promotion has been extended several times and currently runs into January. Acquire the gas cards at the customer service counter at Harris Teeter stores.

If you have a frequent flier account with an airline you use infrequently, you might consider using your miles to pay for magazine subscriptions, which you could give as gifts or enjoy yourself.

This is particularly worth considering if your miles may otherwise expire. Some airlines still have expiration dates on frequent flier miles unless you take action to keep the account active.

Most airlines offer points-for-subscriptions directly through the frequent flier section of their websites, and relatively low numbers of points are needed.

For example, through Delta's Skymiles program, you could get a dozen issues of Outside magazine for 800 Skymiles, while you would need at least 25,000 Skymiles for a round-trip flight.

Looking forward, these sorts of deals are worth keeping in mind when you see opportunities to acquire frequent flier miles, Greenbax and other loyalty rewards.

Reach David Slade at 937-5552, on Facebook or on Twitter: @DSladeNews.