And I thought I was clever for turning the light on for only a tiny split-second to take a picture... (I wasn't writing malware. I put the program on my own laptop before I sent it in to be serviced. http://ecritters.biz/applecarefacility/)
A car magazine claimed they discovered a serious weakness in a particular brand of a steering wheel lock. The company made a series of improvements to the lock and challenged the magazine to demo their hack. The magazine guy approached the new lock, gave it a good hard yank and it came off the steering wheel.
Another one was the Flash fullscreen mode. Flash used to (probably still does) display a hard-coded warning after the app went full screen - obviously to prevent Flash apps from impersonating browsers, OSes and so on. I've seen a demo that took advantage of the fact that the text was an overlay over what the app displayed.
The demo app just went full screen and printed lots of messages in the same font as the Flash warning, all over the screen. The overlay was still visible (Flash made it impossible to hide or cover) but it was basically impossible to read. The demo then pretended it did a Windows restart - it was pretty scary :-)
Serious weakness indeed. Not what people (especially HN readers) usually mean by that phrase!
It's actually kind of amusing to see pictures of you and notice your hair growing over several weeks :)