I've always wanted to create an inventory of my bikes and record the serial numbers, in case one is stolen.
These are most of the bikes that were sitting in the garage when I showed up with motivation and a camera. I missed two of them that were slouching in the corner and there are a few more in the bomb shelter.
Yokota Twin Peaks Tandem - T9108252

Wife's RB2 - 520223

Davidson (I couldn't find the serial number)

Raleigh Sprite - MN02711-131770 (This is hand-etched on the chain guard. I couldn't find a factory SN.)

Novara Buzz - F05031954

Fisher Sugar 293 - WTU013TO 32V

Dahon Helios - TGO111183

Maruishi Wanderer - GH73128

I had this one repainted last winter and it wears mostly new components. I'll install fenders soon. I wish I had a silver rack. If I find a nice one, I'll spring for it.