Please let me know if there are any ways you think I could improve this instructable, and if you have any suggestions for design or constructions modifications.
Shameless Self-Promotion: If you like it, vote for it in the Make it Move contest! Please?
Disclaimer: Multiple instruments are used within the construction of this project that are dangerous if used improperly. Furthermore, if the project is successful and the end result functions correctly, then it will spew hot steam, boiling water, flame, or any number of potentially hazardous substances. Don't hurt yourself, and its not my fault if you do.
Another Disclaimer (New videos=more uses of the engine=more minor injuries=more safety advice): Because of condensation, the method of filling the chamber, overfilling the chamber, the nature of the apparatus, and more, it is possible (read: likely [read: pretty much inevitable]) that you will have some sort of liquid (rather than vapor) discharge from the tubes. In my Engine, the drips from the tubes land right on the hand holding the torch. Although in my experience, this is significantly more likely with the water-filled vs the alcohol-filled Engine, PLEASE take necessary precautions to keep yourself safe. Furthermore, even though the alcohol-filled Engine is less likely to drip, this is by no means a reason to take fewer precautions. The risk from fire not only exists from the rather conspicuous jets of flame from the tubes, but also from the drips which primarily happen at the beginning (before the flame heats the tubes enough to vaporize them before they reach the ends). In short, make sure the area around the Engine is safe, and make sure you protect yourself adequately. One last word of wisdom: don't try to "pre-heat" the tubes with the torch. It's difficult, unnecessary, and if there is any liquid in the tube at all, the tiny amount that you vaporize will eject the rest of the volume of liquid, most likely onto some place where it will cause you pain. Trust me.
More information on Hero's Engine:
A video of my Hero's Engine filled with water: