All of the world's major religions value charity. Zakat, or alms-giving, is one of the five pillars of Islam; the Hebrew Torah is replete with admonitions to be concerned for orphans and widows; and so forth. At this time of year, we are often especially reminded of the needs around us.
A really cool idea was pioneered last year by Nannan Zhang, a prominent member of the LEGO hobbyist community. He asked a number builders to donate their own MOCs which were sold through Creations for Charity. All of the proceeds went to Toys for Tots, to purchase gifts for needy kids. Last year they raised over $3000, and they've already doubled that this year, with two weeks left to go in the campaign. Some of the creations offered for sale this year include Nativity by Thepaleman9
and the Hallgrímskirkja by Bruno and Tanja Kurth. If you're looking for a way to share a little with some kids who have less than you, and get a great LEGO model in the bargain, check out all of the offerings at Creations for Charity.