In ascending order of terrible, they are:
- International Hemorrhoid Day
- International Vegan Day (or is that just the same as the above?)
- Premature Ejaculation Day (I know, I know: all ejaculations are premature)
- Molest A Pre-Teen Girl Day (for Roman Polanski, that’s every day, of course)
and the absolute worst:
- Senator Chuck Schumer Appreciation Day
Your suggestions in Comments, as usual.