I have replaced my tent bag with one of these 68g silyon daypacks, so I always have a day pack available if I've pitched. Never actually used it yet, there never seems to be any desire to walk any further.
http://www.seatosummit.com/products/display/86
I have the exos46 and have used it for a week long trip carrying 3-4 days food.
Edited: 27/06/2012 at 15:55