Quote: "Can I drop you somehwere?" asked the Doctor.
"Ha ha," said the parachute. "Drop me somewhere. That's very funny. Up on the esplanade will be fine, I'll call in my remote from there."
"It might take a while. There's somebody I want to talk to first."
"Doesn't bother me. I can work on my trees anywhere."
The Doctor waded towards the harbour wall. "What kind of trees?"
"I'm designing one that will grow on an asteroid."
"Sounds simple," said the Doctor. "An atavistic silicon outer shell, gallium-arsenic solar cell leaves driving a pico-electric systolic pumping system."
"That part's simple enough," said the parachute. "It's getting it to look like an apple tree that's a bugger."
From the delightful Doctor Who / The Culture crossover by Ben Aaronovitch, The Also People
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Sucrose Octanitrate.
Proof positive that with sufficient motivation, you can make anything explode.