JIT Watch offers the solution to that problem. JIT Watch is a thinking watch…

It is integrated into the user’s Personal Area Network and has the capability to connect via Bluetooth with e.g. cell phones. This provides the watch with the following services: The watch knows the wearer’s actual position coordinates via GPS, GSM-tracking or other techniques. In addition to that the cell phone enables a data connection with the www. Appointments with site coordinates can thus be synchronized. They were entered in advance e.g. into the cell phone or into the computer with a calendar tool like iCal. Furthermore the watch can access web-based navigation-, timetable- and traffic information services.

Ref: Just in Time Watch – Martin Frey (via betaknowledge)