For some reason, the alarm didn't go off when my wife left the store, which is too bad, because I ended up trying to take one off using the tools in my toolbox. I thought I would be able to easily pull the pin out with a couple of pairs of pliers. Turns out it was very hard to take the pin out (I ended up using a pair of wire cutters to chew away bits of the rock-hard plastic until I could get a screwdriver inside and pry the pin off) and I made a little hole in the shirt. I'm too lazy to take the clothes back to the mall to have them remove the devices on the other garments, so I'm asking the readers of Boing Boing to help me out. How do you get one of these things off without mangling my daughter's clothes? Email your solution to me. I'll publish the best one.
UPDATE Most people suggested using a magnet, which did nothing. Another large group of people said take it back to the store and have them do it. Screw that; it's more fun to try it myself than to give up and drive to a loathsome mall. Some people told me to try putting a rubber band between the two pieces and twisting more and more loops around the the pin. That didn't work either. Other people suggested pinching the "nose" part of the clip on both ends with two pairs of pliers, and then pulling out the pin. Nope. Finally, I tried one guy's suggestion to hit the button with a hammer, which would cause it to split the clip open. The only thing that did was pinch the button down against the shirt. Since I already had the hammer, I hit the side of the clip, along its seam. After a few whacks, it split open. Here's what the innards look like. Nothing magnetic in there. I think the people who suggested pinching or bending the clip were on the right track.