A few months ago, my headphones broke. They were Sony MDR-NC6s, pretty cheap but the noise-canceling really helps cuts out the HVAC in a cube environment. They failed when I stood up and the cord was wrapped around my chair. The cord pulled out of the bottom of the headphones. I took them apart, and saw that there was probably enough room to fit a headphone jack in if I used a Dremel and some creativity. The cord now goes out the side of the headphones instead of the bottom, but the repair only took an hour and didn’t cost more than five dollars either. I now use an audio patch cable to connect my headphones to audio sources, and if I stand up with the cord tangled, the cord pops out of either end without damage.
I posted some pictures of the process on Flickr at the photoset Repairing my headphones.
The only real lesson learned is that I wouldn’t use the Radio Shack 3.5 mm stereo jack. It doesn’t grip the cable well. I will have to replace the jack next time I order from digikey.