The Seiko UC-2000 was a smartwatch in 1984. It even had a full QWERTY keyboard, though that admittedly came in the form of a dock the wrist computer attached to. It could still be worn, hypothetically; a larger version was deskbound. Namoki is a website about modifying Seiko watches and offers a brief tour of the device.
The watch tells the time and date, can function as a stopwatch, and also as an alarm clock like most other digital watches of its time. But when coupled with the UC-2100 keyboard, it becomes the "Wrist Information System" that can store memos, keep your appointments scheduled, and act like a calculator. You can save up to 2 memos of 1000 characters each, hence the UC-2000 model name.
I really dig the watch hole's TRANSMISSION CIRCUIT. Fantastic name for a band.
Here's a fabulous photo gallery at Old Crap. Here's one on eBay for $600, though my eye's on the gold edition for somewhat more.
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