I love magnets. I played with them a lot when I was a kid, and now that I am a mature grownup, I use mature magnets: neodymium or rare-Earth magnets. These are like magnets on steroids, superstrong and a ton of fun.
But they're also dangerous. They won't give you cancer or yank out the iron in your blood or anything like that. But because they are so strong, they can attract each other quite, um, forcefully. I've had a finger nicked once or twice by them, and it hurts.
But geez, let this guy's story be a stronger cautionary tale. WARNING: nasty trauma images in there. Don't eat dinner while reading it. Barf.
Still, I'll play with my magnets; I have a little ball magnet about 2 cm across that is way too much fun to roll across a floor. I'd love to find a flat frictionless space to roll it, and see how much it deflects due to torque from the Earth's magnetic field.
But then, I'm a dork. But I have all my fingertips!