The drunken invisibility stories remind me of my year working in Japan. The Japanese LOVE to drink, even those who can't handle alcohol. One grad student would drink to excess whenever we went out drinking...and each and every time there would come a point where his pants came off. Even in the dead of winter with snow on the ground, his pants came off.

I think the alcohol-induced invisibility might also only work in the microwave range and not visible light range.