(Second) Sony LiveView to play with
That's what Sony LiveView can do... and there are actually scripts to control LiveView from linux (good). (One version is in the tui cvs, I actually did partial LiveView emulator, too, but real watch came sooner.)
But... unix does not really have commands one would want to run on wrist... does it? Are there command-line tools to get weather? Public transport info? Navigation?