The Powder Toy

Airplanes (operated by aviators)

CEO (Leads a corporation.)

The atmosphere belongs to a very cold planet with very weak gravity.   The next user is falling into the Venusian atmosphere with no parachute or protection from the acidic clouds.

Wood (What paper is made from)

I happen to be made out of the same materials as the core, so I remain solid due to the enormous pressure there.   The next user is buried in the core of the Sun.

7/10 Decides to put pop rocks in the microwave.   Opens the microwave, only for lava to pour out.

Murderer (Goes around killing people)

However, the operators decide to pull out a fuel rod for isotopic analysis, so I just escape through the opening in the reactor that they opened.   I place you in a sealed nuclear bomb that is n...

I happen to be slightly more massive than the black hole that I'm falling into, so I simply become a larger black hole.   The next user is crushed into a neutron star.

Star (a hot ball of plasma in space, which is where Star Trek takes place.)