Osu! I thought that it would be interesting to post some rather unique bits on the sai for a change, starting with the old favorite of Yamaguchi and Urban Sensei's discussing the use of it.
Known as a symbol of police authority in Okinawa, the police would hold the sai up in front of them when arriving at a crime scene, just as modern officers do with their badges. The sai was originally introduced to the RyuKyu Islands probably by pirates. Definately not as some mistakenly beleive, as a farm implement but as an obvious weapon.
What we know as the sai is actually indeginous to the Indonesian archepelago, and called tjabang or cabang. 
From Malaysia, here we have the trisula. 
Here are tekpi, from a display at the Sultanate Palace in Melaka.
Yours truly in a posture from the kata Arakaki No Sai that I learned while living in Okinawa.Here is something that you don't see every day = a Southern Chinese Sai Form.
Another early version called nunti was formed in the shape of a buddhist talisman, with one prong up and another down. It also has pointed shafts on both ends as seen here in this picture of yours truly, and Dai Sensei, Kow Loon Ong.
The nunti is also often seen attatched to the end of a staff. This is known as a nunti bo.
