10:30 p.m. on December 17, 2011 (EST)
-thin capilene glove liners (want something on my hands, but not much)
-expedition capilene glove liners - the base of what i wear in cold weather. means that if i pull my mitts or gloves, i have full use of my fingers but have something covering my skin. i'll wear them alone if i'm really active and concerned about overheating, eg for nordic skiing and snowshoeing in the woods, so long as it isn't too cold.
-OR windstopper gripper gloves - uninsulated fleece windstopper gloves, great if you need to use your hands. sized so i can wear either pair of capilene liners underneath. very durable; kind of hard to dry in the field.
-shell gloves lined with primaloft - a medium-cold solution if i need some use of my hands. mine happen to be marmots, but there are several brands. the warmer versions will have removable primaloft or fleece liner but i wanted to save some $; if it's really cold, i don't trust gloves.
[the one hole in this array is that i don't own gloves suitable for really cold weather. that's a personal preference. there are some pretty warm gloves out there, eg the black diamond guide gloves, if that suits you).
-dachstein wool mitts - aka boiled wool mittens, thick, densely-woven wool. my oldest winter mittens, used to wear 2 pair under shell overmitts as my coldest-weather solution. large enough to wear with capilene liners underneath. i carry them mostly as a backup at this point. worn with the liners and a shell overmitt, they work reasonably well for me down close to zero. somewhat resistant to wind and moisture, so they can be useful even without shells. very hard to damage. plus, they looked really cool when clint eastwood wore them in The Eiger Sanction.
-old REI shell mitts with primaloft liners - my main deep winter backups. rei waterproof/breathable shells. years old, still good to about -20 with liners.
-OR alti-mitts - my main deep winter mittens. thick removable primaloft/fleece liner, under gauntlet gore tex shells. nicely articulated thumb. with liners, happy fingers in -70 degree wind chills.
one point of emphasis - for really cold weather, make sure your shell overmitts or gloves have leashes, and make sure you use them on your sleeves. if your gloves get dropped or blown away, they don't do any good. even with the leashes, carry a real pair of backups.