how about making them a beautiful quilt and gifting an electric mattress pad or eletric blanket to go along with the quilt. there are dual controls on either electric item so one can crank up the heat and the other can save the additional electric, all under the beautiful quilt that you made them. :-)
i got my electric mattress pad last winter and i love, love, love it. heated sheets, heated feet, all in the winter time; who wouldn't love that? :P