Gift cards — the latter day gift certificates — have become big business, especially for restaurants. Businesses love them. They get money up front for something that may not be used for some time; the people using them don’t always use the full amount, leaving unused dollars on the card and in the restaurant’s bank account; or perhaps they are enticed to come to the restaurant for the first time because of the card and they’ll spend more than the gift amount, and perhaps become regular customers.

And sometimes people don’t use the cards at all, or they lose them.

But gift cards are an iffy propostion, especially in today’s economic climate, whether you’re buying them from a large national chain or a small local eatery. Because if the restaurant closes down, that piece of plastic is worth, well, about as much as a piece of plastic. I wonder how many people are holding gift cards to Bennigan’s restaurants today. Or Steak and Ale. Which restaurants will close next? There’s no telling.

So if you’re giving gift cards this holiday season, try to choose a restaurant that’s reliable. I think I might feel a little safer with, say, a Darden restaurant knowing that if they were to close one of the concepts — and I’m not saying they’re thinking about it, but didn’t they still own Smokey Bones not so long ago? — they will generally honor the cards in one of the other concepts, Olive Garden, Red Lobster or such.

Be leery of businesses that are encouraging gift card purchases. That’s sometimes a sign that they need to raise some fast cash. (Since I started typing this I’ve received an e-mail from a local restaurant touting its gift cards.) I’ve seen it happen many times, even in better economic climes, that a restaurant pushes gift certificate purchases then takes the money and runs. Just try collecting on a $100 gift card in bankruptcy court.

And if you receive a gift card, don’t put it away and think you’ll use it later on. Make a reservation to go for dinner right away and spend that money.