Cherenkov radiation gets you wicked high, man.

[flewellyn]

So, the other night, I had a strange dream in which a science teacher was explaining about how light travels at different speeds through different substances. Some joker in the class asked "how fast does light travel through marijuana?"

Said the teacher, "About three miles an hour. And when it makes it through, it can't be bothered to care if it's a particle or a wave."