An idea I found and plan on stealing from another site is to use the heavy aluminum disposable baking pans for your kit. The heavy duty pans do not spring leaks even after several foldings (so I've read)and they fold very compactly. One, or two, of the small 1 quart size pans can be brought to use to boil water in, folded square or into a cup shape under your water bottle, etc. One of these could also be cut up to make the lid for your existing Nalgene bottle space saver cup. Like I said , I haven't tried these yet, so YMMV, but I plan on testing them out. I already have a Snowpeak titanium cup that fits under a Nalgene, and several other small pots like the GI canteen cup. ONe always goes in the pack. The disposable baking pan foil thing will go in a larger PSK type deal where space/weight is an issue.