As the clock ticks down for procrastinators this paper becomes more and more important.
From Harvard Business School via Harvard's DASH:
AbstractFive studies investigate whether the practice of "regifting"-a social taboo-is as offensive to givers as regifters assume. Participants who imagined regifting thought that the original givers would be more offended than givers reported feeling, to such an extent that receivers viewed regifting as similar in offensiveness to throwing gifts away (whereas givers clearly preferred the former). This asymmetry in emotional reactions to regifting was driven by an asymmetry in beliefs about entitlement. Givers believed that the act of gift giving passed "title" to the gift on to receivers-such that receivers were free to decide what to do with the gift; in contrast, receivers believed that givers retained some "say" in how their gifts were used. Finally, an intervention designed to destigmatize regifting by introducing a different normative standard (i.e., National Regifting Day) corrected the asymmetry in beliefs about entitlement and increased regifting.
....MUCH MORE
Possibly also of interest:
"The Deadweight Loss of Christmas"
The gap between what was spent on Christmas presents and the utility the gift brought to the recipient.
Originally published in the American Economic Review, here's a copy stored on Amherst's servers. (9 page PDF)
TL;dr - give cash.