Water Bottle Parkas
So what to do? Anything you can think of, really. To the extent that you can carry enough fuel, use it first and foremost to melt snow for drinking, and then use the remaining fuel for food preparation. I've found that insulated water-bottle jackets such as Outdoor Research's Water Bottle Parkas ($17, www.orgear.com) really work very well. Also, many jackets and parkas designed for hardcore mountaineering have big internal pockets for carrying water bottles close to your body. Mountain Hardwear's Tenacity Descent Jacket ($415, www.mountainhardwear.com), for instance, is a Gore-Tex piece with an internal water-bottle pocket. Feathered Friends' Icefall Parka ($385, www.featheredfriends.com) is an expedition-weight down parka that has two water bottle pockets.
I won't argue with the notion that even two water bottles, kept in their liquid state by holding them close to your body and inside a down parka, is barely adequate for a long, cold, high summit attempt. All you can do is try to drink all the water possible before setting out from camp, carry all that's reasonable, and do everything possible to keep it liquid. Then you simply have to tough it out.
Read "Break the Ice" from the January '04 issue of Outside for six hydration systems engineered to stave off the worst effects of the sub-zero freeze.