Funnily enough, I don't. No lucky socks/underwear. Not about to avoid a black cat (for obvious reasons) and broken mirrors only mean a bloody horrid mess to clean up.
Being a bit of a dizzy fecker, I occassionally mislay it (ie put it in another pocket), and have to search around (semi)-frantically, like something bad would happen if I lost it.
yep. that's weird.
I avoid walking under ladders. That's more because of falling objects than a superstition though.
No point tempting fate.