From CNN Correspondent Lori Waffenschmidt

(CNN) -- It's the season when many people are giving and getting. It's also the time to donate to charity, and many travelers are giving the gift of flight.

"Say, for example, you don't have enough miles to claim a trip anyway. You can give your miles to charities that are set up by the different airlines," said Chris McGinnis, business travel consultant for CNN.

According to InsideFlyer magazine, 162 million frequent flyer miles were donated to charity last year -- an impressive number until you realize that 32 billion miles expired without being used.

"These charities can take the miles and fly ill children to hospitals; they fly volunteers and physician researchers all over the world," said Rachel Hill, a spokeswoman for the magazine.

To get more specifics on donating miles, call your frequent flyer programs.

"Sometimes you get to designate the charity; sometimes you donate them to the program and they decide which charity gets the miles," said Nathan Lump, a spokesman for Condé Nast Traveler magazine.

If you're worried about blackout rules and seat limitations, you can relax. Most airlines waive those restrictions for donated miles.

But don't expect recognition for your generosity when tax time arrives.

"Miles aren't considered money so you can't do a tax write-off," Hill said.

But you will get the satisfaction of knowing your frequent flyer miles were put to good use in the spirit of the season.