Here's an unusual wedding present - a puzzle box that won't open until
> it is taken to a certain location in the world!. The Reverse Geocache
> Puzzle is based on an Arduino microcontroller.
>
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Neat. Reminds me of my wedding day which was also a Geocaching event!
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(photo links have now vanished) I had to vanish during the reception dinner to go find one of our presents in a cache half a km away.
I think I was the first in Sydney caching with an electronics waypoint decoder back in the day.
Ah, Geocaching, those were the days...
Dave.