Machine gun development
I was trying to think of something I could invent that would make a lot of money and in about a minute I thought "Maybe a machine gun that runs on gasoline explosions instead of gunpowder explosions!"
There would be advantages to not having the powder and cartridges attached to the bullets. You might also be able to control the rate of fire with the trigger, and step on the gas if things get tense.
I do have a lawnmower in the shed and the gas tank from it would save on the cost of developing the weapon. It's such a nice feeling when things start falling into place on a project.
I mentioned this idea to a couple of people I could trust and after a bit of discussion one of them said: "Yeah, sure. Some cold winter day you'd see a guy on a hill jerking the starting rope trying to get his going."
Well OK, maybe it wouldn't have been the greatest idea to ever hit the patent office.
Ad: Join Amazon Prime - watch over 40,000 movies, 30 day free trial