Grant Erwin wrote:
Is there any safe way to open a still-pressurized can of spray paint with a
completely plugged nozzle, to get the paint out so I can brush it on?

How about if I made a tool e.g. drilled a small hole in a Popsicle stick or
tongue depressor, turned the can upside down, removed the nozzle, and depressed
the valve stem with the hole aligned? Maybe the air would all come out and leave
the paint inside, then I could cut it open any way I wanted reasonably safely.

Ideas? Experience?

Secure the can in a vice, base down.
Put bucket closely under vice.
Hammer small nail into the bottom of the can (wearing gloves).
Nail may shoot out (not violently) on its own, or may need to be pulled
out.
I doubt that the paint will work for brushing.
The absolute pressure inside the can is small - there is no risk of it
splitting, unless you heat it first to 50C or so.