Everyone knows it's the thought that counts. If you found yourself uttering "You really shouldn't have" a little too sincerely on Christmas morning however, it's time to think again.
Regifting -- the act of fobbing off an unwanted gift on someone else -- first rose to fame on an episode of Seinfeld.
And it's so popular that online marketplace eBay has dubbed the rest of this week "National Regifting Week".
Over half of all adults will regift at least one item that they found under the Christmas tree, according to a new survey.
Regifter or regiftee, here we reveal the golden rules of how to do it without getting caught.
* Unwrap it first
Just because it's shaped like a selection box, and rattles like a selection box, don't assume that it's actually a selection box.
Before passing on your unwanted pressies this festive season, at least have the decency to unwrap it first.
Who knows, you might even be pleasantly surprised to discover that it's not entirely crap after all. If not, then by all means, go for it!
* Don't keep it in the family
Regifting is a bit like playing an elaborate game of Six Degrees of Kevin Bacon -- if you keep going long enough, it eventually circles back to the original gift-giver, and then you're in trouble.
To avoid any awkward conversations about how your Auntie Mary's new casserole dish looks exactly like the one she gave you for Christmas two years ago, be sure you know who gave it to you in the first place, and never regift within your circle or family or friends.
Regift me once, shame on you.
Regift me twice and you might as well call it recycling. Regifting isn't just an opportunity to cut down on your bin costs for 2014. Only pass on new, unused items that the person actually wants or needs.
* Have a heart
Not even the Grinch would regift the toilet-roll Santa lovingly crafted by his five-year-old niece in art class. When it comes to regifting, hand-made, monogrammed or otherwise personalised presents are a definite no-go.
Lingerie or slippers that just so happen to be in your exact size are a danger zone.