You can buy ESBIT fuel from Campmor. It is hard to ignite, but is more stable than it's TRIOXANE cousin . Expose both to the air and the Trioxane dissolves while the ESBIT looks like a troll caught in sunlight. Triox does seem to produce a hotter flame, but this is my anecdotal observation. You will improve the stove's efficiency with a windscreen. I cut two rectangles from a soda can, bent into a L and trimmed to fit inside. Place them along the exposed sides and one tab will bring a G.I. canteen cup to boil. If you rig some manner of container lid the efficiency again improves. Watching most of your heat being drawn off the open top waiting for the hot chocolate is demoralising. That piece of aluminum foil in the PSK? perfect <img src="/images/graemlins/wink.gif" alt="" />