I have a worn out Planet Bike LED Bike Light Mount. It lasted many years and now it simply doesn’t click the lock closed dependably. Online costs for a new mount seemed too high, appropriate, and yet, functionally, not a direction I wanted to go. I couldn’t use the bike light as a helmet light while using my much bright Cygolight from my non-commuting bike.
I am going to try this Instructable How to make bike lights with sugru + magnets and see how it works.