inste-edit: I know I'm being pedantic and a reasonable concentration of hydroflouric acid is what you were talking about.
There was an article somewhere about a 1 tonne spill on chlorine triflouride
+1. When you know what is going on inside you can get a much better feel for what the car is doing.When you are cruising along, if you back off the accellerator a bit you can feel the whole drivetrain go 'loose' (If you back off a bit more you will start engine braking). This the backlash in the gearbox & you will find you can pop it out of gear without the clutch quite easily. Putting it back in without the clutch is best practiced on an enemies car.
a fred is a bit bigger but also good.