Slick looking, right? The Data-2000 could store memos (well, two of them) and calendar entries and also acted as a calculator. You had to make use of the clip on keyboard but hey, that was part of the fun. Seiko was pretty prolific in the smartwatch arena in the 80s. It also launched the UC-2000, the RC-1000, the Memo Diary and the UC-3000 within a year of the Data-2000.

1983: Seiko Data-2000