Potlach takes its title from the name , in native american's society, of a ritual and no commercial exchange of goods. A kind of challenge of gifts between rival clans.Non buyable goods distributed by "Potlach"are needs and inedited issues.Only resuming thoose needs and issues can constitute the back gift. Video Sources for cinelerra (cv.cinelerra.org) are under the same license as the video: http://www.megaupload.com/?d=DY3I7J35 http://www.megaupload.com/?d=CU4TWKM1 http://www.megaupload.com/?d=776B7WYD