My hometown is on the border of the Sussex and Saint John, New Brunswick graticules, but I now live in Toronto so if any geohasing happens, it's probably going to be there and not New Brunswick (except on holidays and special occasions).
I spent most of December 2008 in the Ahmednagar, India (19, 74) graticule, where I spent most of each day wandering around the countryside with GPS in hand trying to find locations generated by a computer algorithm. No, this was not geohashing, but, science. While I kept an eye on the area's hash points, and the idea of falsifying data so that one of my targets was coincidentally the same point as the day's hash did cross my mind, phrases like "academic integrity" and "wanton waste of government resources" held me back. Oh, but it would have been nice to do not only a virgin graticule, but (as far as I can tell) a whole virgin country.