I have used my Jetboil Ti by setting it in the snow, melting snow (I know it's not recommended) and boiling water down to 20 degrees at 12,000 feet elevation. It is a little slower in those conditions, and the snow tends to freeze to the bottle, but it works and is a quick, light, simple rig to boil water.
When melting snow you have to keep pushing snow to the bottom to keep it from running dry while melting snow. I usually add a quarter inch of water first before melting snow. I have tried to eliminate a stove from my pack, but just melting snow for water has saved me from heading down the mountain in search of water many times.
