To regift is to "give an unwanted gift to someone else; to give as a gift something one previously received as a gift."
"Well, why not?" ask the folks at Tiny Choices. "If you were given a gift which you'll never use, passing it along to someone who will just makes good sense. Also, it's sort of the middle R in the 3R Mantra, reduce, REUSE, recycle. First, you'll avoid buying another item (and all the associated pollution that item would cause). Second, you'll avoid spending some money (and who can argue with that?)"
MP Dunleavy at MSN Money can argue: "Certain items are a total, dead, instant giveaway that you not only are regifting, but you're too lame to put any effort into it: candles, soap, random books, mysterious CDs (unless your brother wants the hip-hop version of "Man of La Mancha"), obscure software, cheesy jewelry, scarves (do we not all own a scarf?), fruitcake, pens, cologne, boxed sets of extinct bath products (Jean Nate? No, no, no), videos or DVDs obviously acquired on a street corner, socks and any appliances or electronic gear the giftee would be puzzled to receive because they probably just got rid of it (including hot-air popcorn poppers and anything with a cassette deck in it)."