Sleeping in a traditional kilt or poncho or cloak could be a fun thing to try in winter. Again, not a real weight saver, or $$$ saver either if your fussy about your material, but if you can get a hold of some suitable material at a reasonable price and put an idea together you could make a go of it, and end up looking rather dapper by day, subject to the eye of the beholder.
http://www.historichighlanders.com/belted.htm

If you can find a comfortable way to hike in 4-8 pounds of clothing by day, and sleep in it by night, you might also be able to reduce your pack to something for carrying food. If you really want to go traditional, as in way back traditional, maybe a pack like this...
http://www.primitiveways.com/pack_frame.html