why not combine (Score 1)

Why wouldn't you combine the GPS and digital Signature ideas. You would only want to send your geographical location as proof of you requesting to do something so why can't you when you request this, also put in a little password. If the password is right you can assume you and your computer at the same physical location which is whatever the GPS system says. Alternatively I am sure you could find yourself a small enough GPS you could have surgical implanted somewhere and if you are a little lacking in one particular area.. well......