Hello there, Thank you for the timezone database — it is a phenomenal resource. The problem I would like to solve is that of having to ask a user of a web-app for their timezone. While there is no way to directly query for the user's timezone, the javascript engine in their web-browser is capable of telling me the offset from UTC at any date. It seems like, by selecting some number of dates to query, I should be able to gather enough information to uniquely identify any given timezone (or at least make a very good guess for a large proportion of the user-base). Before I embarked on doing this, I wanted to ask if anyone has seen a similar attempt in the past? Are there some "gotchas" that mean that this isn't actually as feasible as I naïvely hope? Conrad