Forget the fruitcake: Give skydiving lessons

"He always talked about it kind of longingly, and I knew it was just the kind of thing he probably wouldn't get around to taking the initiative to do himself," says Vannice, 29, a doctoral student at Johns Hopkins School of Public Health in Baltimore. "We rarely pamper ourselves with nice or new experiences."

Still, as with any gift, givers of online daily deals have to proceed with caution.

They come with expiration dates, and if your brother keeps hectoring you about whether you've taken that hot air balloon ride, it can get awkward. Plus, you can always take a necktie back, but returning a day of zip-lining is tricky without a time machine.

And the deals are basically coupons, which can carry a stigma. LivingSocial offers what it calls virtual gift wrap — the recipient gets his or her deal in a fancy envelope, and without seeing what the giver paid. Groupon recipients only see a description of the offer, and sometimes the regular price of the experience.

Then there are other gift faux pas to consider.

Aaron Cooper, whose job title is chief of gifting at Groupon, said givers should make sure to tailor their gifts to the person so it's something they can use. Not, say, skydiving lessons for 86-year-old Aunt Bertha.

Maire Griffin, a LivingSocial spokeswoman, agrees: "You're not going to give anyone Botox. If you are, you're not going to be their friend anymore."