...with a very low power laser which is too weak to cause harm.
The next user is trapped inside the core of an operating nuclear reactor. If the temperature doesn't kill you, the extreme neutron flux will, by converting your body into radioactive isotopes.
A noob walks into the power station and drops all the boron rods and accidentally turns everything off.
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The next user accidentally wakes Stalin up while not being his comrade...
I proceed to use the technologies I just used to awake Stalin (I mean, he died in 1952) and create a zombie army and overthrow the Communist regime.
The next user suffers from a massive heart attack.
The asteroids are too small to severely damage a ship which is made of layers of boron carbide, silicon carbide, boron steel and rubber duckies.
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The next user is trapped in a never ending paradox
Eventually an outside influence breaks the paradox.
The next user is attempting to enter orbit in a ship made of materials like boron steel, layered thickly, making the ship too heavy to achieve escape velocity.