hmmm... neoprene socks work differently -- you get wet, but not cold. Whereas booties try to keep you dry.

Those I've settled on are the NRS. Notice that they are called wetsocks. 80g/300ml. For the record, the Raidlight mitts (synthetic shell designed to keep you dry) weigh 20g and should pack at well under 100ml. I'll update when I receive them (as is usually the case, easy to find the weight, but limited to no information on packed size).