Seiko WristMac

The Seiko WristMac (RC-4500) is an early smartwatch from.

Description
Introduced in 1988, the WristMac was based on the 1985 Seiko PC Datagraph (RC-4000) in a modified plastic case that was available in various colors. It featured a C-compatible serial port, and could communicate with a beige-era Macintosh through an available LocalTalk port. A HyperCard stack was developed by Ex Machina to sync alarm, calendar, and contact information with the watch.

System requirements

 * System 6.0 or later
 * HyperCard 1.2.1 or higher

Computer journalist had apparently managed to get a gold Seiko RC-4000, priced at around 200 in 1991, to also sync with the WristMac software.

History
On August 28, 1991, a Macintosh Portable sent the first email from space while aboard the  during  mission. The astronauts also wore Seiko WristMacs which could be synced with the Macintosh Portable to load short 2-line reminders that could be displayed on LCD of the watch.

Collectibility
The Seiko RC-4500 and 4000 series are not particularly rare, but can fetch hundreds of dollars, depending on condition and the presence of original packaging. On November 22, 2021, a boxed Seiko RC-4500 specimen, complete with the rarer original WristMac software package, was put up for sale in an auction which will close on December 18, 2021.