You'd think the worst that could happen if an ink pen exploded would be a giant blue stain on your favourite white shirt.
But take a look at this video that shows how easily a simple ballpoint pen can be converted into a dangerous bomb using a binary explosive. Don't worry, it doesn't reveal exactly what materials are involved, just makes clear that it's not terribly difficult.
That was, what, a tenth of the material the pen could have held? Suddenly, the stories about Umar Farouk Abdulmutallab's explosive underwear don't seem so funny.
Anyone ever had trouble getting a pen through airport security? We'd like to hear if you've ever been stopped because of your pen.