There are a massive list of things that I would never do. They typically fall into a hierarchy of different things.
Impossible things. - Create and destroy matter or energy.
Improbable things. - Win the lotto.
Impractical things. - Dedicate my life to reading every book I can.
Things beyond my ability - Run a three minute mile.
Things I never would think of doing - Escalator Spinning.
This is the coolest thing I would never have thought of.