This is where one manipulates the stock market such as to cause it to open on a target number, forcing a pre-determined geohash location. Because the DOW will only change by a certain amount per day, the range of possible future geohashes can be preguessed. From this range, select one - and then play the stock market to target that exact opening number.
Only the richest and most stock market savvy geohashers are likely to successfully hack the geohash. Those who do are eligible for the Bill Gates Achievement.
- Please refer to the Lazy Geohasher implementation as a useful tool to help you geohash hack.