I am surprised that no one has developed a mod which uses a mercury switch instead of a mechanical firing button. When our mods are vertical, we are not planning to vape on it, but when we tilt the mod we are usually planning to take a vape. Why not just use a mercury switch. It would allow the mod to be much shorter. The switch can be biased to fire at 45 or 60 or 75 degrees. I bet it will be used on a VV/VW first but there is no reason it cannot be used on a mech. Just a thought.