I picked up a pair of old crystal-based headphones at an antique shop in Huntsville a few weeks ago. Now, there are those who would loose their minds at me tearing up an old antique, but fuck it. They didn't work anymore. Not like an old sextant or something that still did its job but there were new ways to do it, I mean these things were just junk. Attractive junk, but junk none the less. So, I retrofitted them with modern speakers and cabling and now they work great and look cool, to boot.
I more or less followed the advice and design Molly Porkshanks used in her headphone mod, but I followed through on the bits she said she didn't have the patience for. Which basically means I desoldered the speakers from their wires, ran them through a boot lace, and resoldered the connections. This allowed me to run the wire through an existing hole in the ear cups without making any new cuts.
Anyway, I wouldn't really count these as a project in unto themselves, but they are definitely a nice addition to the collection. And they are wicked fun to wear at the office! At some point I'll try to take a decent picture of them, but that will probably wait until I've got a finished project that will make use of these headphones.