Blowing my nose into a handkerchief in public.
I was at a hotel swimming pool along with about 50 roaming kids. Had a bit of a cold that day, so ripped out a handkerchief to blow my nose. What happened next was about 6 kids come up to watch me blow my nose... Very bazaar I thought.

Probably because when I blow my nose it's like a trumpet and I use a handkerchief rather than tissue. In many Asian countries, everyone uses tissues....
Be warned
