In the spirit of Christmas, there seen to be quite a lot of free music offered by a number of bands/musicians:
Bradford Cox recorded 5 versions of a new Atlas Sound Christmas song entitled "Artificial Snow", go here to download all of them.
Merry Christmas from Anamanaguchi with an awesome cover of Mariah Carey’s "All I Want 4 Xmas Is U"!
Anamanaguchi: All I Want 4 Xmas Is U (Mariah Carey cover) [wicked-cool song]
Klaxons released an EP called Landmarks of Lunacy and you can download all 5 tracks from the EP for free here.