I really love stirling engines. Even built a model that works. (barely)
And the thermoacoustic ones are genius on top of genius. I just hope this technology really matures and gets affordable.
Till then one can still have a small thermoelectric generator.
Why does your bag say "bombs"? The reason I ask is that my bag says "tiny ads" and it has stuff like this:
Your suggestions have been mashed into the PIE page - wuddyathink?