Bertho posted his blinking earring in the project log forum:
An idea of a blinking earring was born while talking at the local hackerspace. Inger was playing with harddisk parts and wanted to make blinking earrings. She has been doing workshops making jewelry from old computer parts (very, very nice; she is not an engineer/technician).
Well, we were discussing a more advanced version and this is what I came up with and how it looks (31mm outer diameter)
The paperclip trick was inspired from matseng’s idea (many thanks!) and it uses a standard cr2032 battery.
Very nice !
I’ve made a bit different blinking earrings based on a 555 chip.
Have a look:
http://hwmayer.blogspot.com/2010/10/555-earrings.html
Nice deadbug-job. You have a small task when the batteries need a change. I went for features where you went for implementation.