This is my first post here on HF, but I've been backpacking for 17 years, and camping for 25. I feel like I have lots of experience, but I understand the need to balance the confidence that comes from experience with caution, especially when dealing with real cold. Living in the Southeast, I don't deal with much below 0*F, but I've been out several times in that -5*F to 5*F range (at high-for-the-east-coast altitude). It is definitely a challenge. That being said, I love the winter camping. The trails are sparsely populated, the landscape is beautiful, and I get to play in the snow. This is big having grown up in Alabama.

Seeing as how we've pretty well covered the fact that the cold is deadly and nothing to be taken lightly, and since Cannibal was pretty vague with his title, does anyone mind if we also discuss the hammocking gear necessary for surviving a 0*F night?

Here's what I've been thinking about lately:

I promised myself that from April 2012 - April 2013 I would go on at least one four day backpacking trip per month. I have so far kept this promise, and will continue through the winter. I plan to hit some high elevation areas in TN/N.C. this winter (likely the Smokies and Shining Rock Wilderness) during January and February, so the chances that I might see temps near the 0*F range are decent. Would any of you consider hammocking in that scenario?

Here's what I'd definitely take with me:
-Homemade hammock/bugnet/silnylon tarp setup that gives full coverage for wind.
-Western Mountaineering Ultralite 20*F down sleeping bag
-Homemade, full-length, nearly full-wrap down underquilt good to about 20-30*F

And here's the additional stuff I'd bring to assure survival in case it got bad:
-Homemade hybrid down quilt/bag tested warm to 30*F for use as extra top insulation
-Big Agnes Q-Core Insulated air mattress as extra bottom insulation
-Soon to be made 3-layer Insultex insulated hammock sock

Do you guys think this would make for a sufficiently warm setup if I encountered 0*F temperatures. I ask because I wonder if I even want to bother trying to stretch the hammock that low. I will be out in those temps regardless, but I just have to decide on tent or hammock. I've already sworn to myself that I'll never sleep in a tent again unless I'm above tree line. I'm considering giving it a shot. I truly think I'd have enough insulation, but I would almost certainly carry a tent just in case. If I started getting cold, I could get in the already setup tent, and I'd have a warm pad, and three layers of down (sleeping bag, quilt, underquilt) to layer on top of me.

Thoughts?