Just wanted to reiterate what most on here already know. There are always little pieces of gear that don't seem very important until you put in the trail time and you find yourself going for them all the time. Trekking poles are like that for me, headlamp (was like pulling teeth to convince my GF to pick one up instead of her little pocket flashlight. Now she wont shut up about it)
Reflectix has moved itself into that category for me. It weighs practically nothing. It's really about as little bulky as can be compared to CCF. I bought one 25' roll for 15.00 at Home Depot (found in the housing insulation section). That's 4 bedrolls and enough for cozies for a cook set. Cheap.
It's a great portable bail-out if you hit weather that's colder than the gear you brought was made for. It's water-proof. Use it as a pad outside of your hammock. You could probably even use it as a leg or arm brace if you needed it on the trail. However, using it around the campfire at night was the bread and butter for me. Shoes off, laying alongside the fire I was remarkably comfortable not having to sit up and not having to lay on the damp ground. In the winter it worked just as well in this function, just with shoes on
For those who haven't experienced the utility of this material, you're missing out. This will be a regular in my pack for the foreseeable future.
Remember, Housing Insulation, not the Plumbing section. At least not at Home Depot.