Granite Gear DreamSack $18.95
I bought one of these. Have not used it yet though. Here is the description from amazon:
Do you want the comfort of a real pillow without the weight? The dreamsack is an ultralight sil-nylon stuff sack with luxurious fleece on one side that is shaped like, well, a pillow. Stuff it with something soft like a fleece or down jacket and snuggle in. Sleep well!!!
It's all about the pillow
I have a small thermarest pillow. Not ultralight but I canoe camp so I don't care. Perfect for under my neck. http://www.rei.com/product/719843/th...essible-pillow