Filter stuck on lens
Don't squeeze the filter between your fingers it distorts it making it harder to twist. Place your palm over the filter and press while twisting, works every time for me.
That does usually work with standard filters, but it's not a viable technique when the front of the filter rotates, e.g. a variable ND filter or circular polariser. I had a hell of a job getting a CP filter removed from a used lens that came with one stuck on.