Is there a lat/lon database that contains the timezone boundaries? With a lat/long TZ DB, users could input their city or zip (or heck, if they know it, their lat/lon), then the app would associate the user's lat/lon with the TZ lat/lon and output the TZ (if the user's lat/lon was not found, the app would just fall back to the continent/city names).
To take it one step further, mobile apps with GPS have real-time lat/lon, so getting the TZ should be easy... How useful such an mobile app would be is another question. Jim
