What's the funniest or dumbest thing you did?

I spent several weeks listening to my home theater DVDs in Dolby Pro-Logic . . . . I always just assumed that the default setting on my new Sony DVP9000ES was 5.1, but it turns out that the factory default is a downmixed PCM signal. What makes it REALLY stupid is that my receiver always indicated "Pro-Logic DVD," and I thought that it was really weird that the receiver would say that when it was playing a Dolby Digital 5.1 DVD . . . .

Oh no, Twl! You'd sold all your LPs last year? Wish I was here last year! Man I missed the boat (*&(*&:-(

When I lived with a roomate about 20 years ago, he had a GAS Son of Amp, and some speakers that someone made. Well,
they just didn't have the midrange that my Fried speaker's had so I hooked them up too. Well, back then the revolutionary "Polk speaker wire" had just came out. so that's what I used. Needless to say, the one channel went
out. So, we ended up sending it to Gasworks and had it repaired and upgraded. So, they send it back, and what do I
do, but the same darn thing...Hooked up my speakers again! Bingo! It went out again. Well, Gasworks didn't want to keep
fixing it, so after a little discussion they found out I had used the Polk wire. "Very Bad Stuff", impedence fluctuated all over the place. So know the primary use for this revoltionary wire is to tie down loads to the dump!

Had to think about this one ... so many choices! Well here's some genuine stupidity for you:
Was troubleshooting an amp that I had built myself completely from scratch. Somehow I connected the output test leads back onto the meter that I was using to monitor the input. Powered on - went into total oscillation, & then kapow a cap exploded. I was so royally ticked at myself!
Turned out to not be so bad after I decided to gut the whole thing then redesign & rebuild it. The result was quite rewarding.

Grade nine electronics class; I was trying to take a mono turntable, install a stereo cartridge, and run stereo inputs to a tiny Radio shack amplifier. I wound up wiring AC power into the turntable cartridge. When the electronics teacher saw what I had done, he laughed so hard that he had a seizure and had to be taken to the hospital in an ambulance. Do I win???