What's the stupidest thing you've ever done?

Class.

I had a fight with my friend at the back of a church once. During a service. We were out the back messing around. I pushed him, he tripped and put his head straight through a big stained glass window. I think we were the first people ever to be thrown out and barred from a church. My parents were not happy. I did warn them though. That was the last time I ever went into a church, except for weddings and funerals.

Haha I did something similarly offensive in high school, I went to a jewish school, and in RE lessons the rabbi's used to get a torah out on the main table at the front, I started having a play fight with my mate and it got semi-serious after he winded me, I then without thinking threw him across a desk and onto the Torah, I don't think we helped our case by bursting into laughter right after I did it, needless to say our parents got called in and we almost got chucked out.