I froze my butt off on a trip to the Adirondacks last October because I was using a cheap bag from a big box store. I finally spent $200 on a proper 15-degree down bag and the difference is night and day. Anyone have a good trick for keeping your feet warm in a mummy bag?
Wasn't there a study about how damp socks make you lose heat faster? So @jade47 is onto something with the clean pair idea, since they're usually drier. It's a small thing that actually makes sense.