As many of you know (ad nauseum, probably), I tend toward the more unusual or uncommon vintage pieces, especially early digitals. I got lucky today with this Seiko O634-5019 from 1976. The world's first digital chronograph:
Complete with original box, instruction booklet, and guarantee booklet/proof-of-sales dating the original purchase to August 21, 1976. The watch is a little scratched, the buttons need cleaning, and the polarizer film has aged to a golden brown, but it works and keeps time. Nice chunky bit of 70's horological history for my collection.