Mark Freeman wrote:
Maybe if you've been practicing for a long time it would be excellent stuff.
For those who have not done it routinely, an excellent kiai practice is the fundatori/furatama exercise. The exercise is closely related to kotodama practice, and also has relation to sword-work and the "Ey!" "Yah!" "Toh!" of movement. I have been in number of aikikai dojos that do not do it routinely, so it may be unfamiliar to some.
It looks a little silly, a bunch of people shifting forward and back in time with one another and thrusting their arms forward ("EY !") and back ("SA !") like rowing a boat. But it really does work. The more people doing it, the less self-conscious you are, and the more you can work on blending focus, which is the heart of kiai, and of aiki.
If you have ever been to Japan and seen the kinds of, shall we say, - idiosyncratic - mass exercises that have been done in the corporate world, fundatori/furatama is fairly nondescript. For an howling example of the uncritical acceptance of this kind of thing in Japan: see this clip recently sent by a buddy of mine, which is a recruiting commercial (swear to God) for the JMSDF (Japan's not-a-Navy)