I don't carry much in the way of extra clothing and so have nothing to put into a stuff sack to put underneath my knees. I take this pillow from REI:
http://www.rei.com/product/766035
[IMG][/IMG]
Weighs about 4 oz and can be adjusted for size. I also use it when on my side under my knees again. I do this per Warbonnet's advice and it's made a big difference in staying asleep.
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