Speed sailing is all about going fast.
There are now 2 categories of speed sailing event, the 'traditional' method which is to sail down a measured course and calculating the average speed from the transition time, and the new approach which involves the use of a GPS receiver to measure the speed of the sailor.
The former method is the one used for formal world speed records - the distances involved include 500m and 1 nautical mile. To attempt these records involves a specially prepared course with suitable timing equipment, official representation and lots of luck with the weather.
Participating in this type of event usually involves significant commitment of time and money with no guarantee of satisfaction let alone success. It tends to be limited to a small group of dedicated individuals or people with commercial backing.
GPS speed sailing on the other hand can be done anywhere, anytime by anyone and only requires the use of a suitable GPS device, it's very democratic.
Current challenge running includes NZ teams http://gpsteamchallenge.com/