My dad gave me his Texas Instrument 101. He worked for Texas Instrument for a while and had bought one. When he got tired of replacing the batteries he gave it to me. I seem to recall that it had been an expensive watch,. It disappeared
(Not mine, pictured borrowed from the web).
The first watch I bought was a Seiko Sports 100. This model in fact:
This particular one was a gift from our own Dan Byers, my original is in pieces as the battery leaked and I took it apart.