A friend who spent some time in the military told me about a silent language in which the hands are signed in short, rapid bursts. Really, really rapid bursts, actually.
I've seen videos of both wing chun and speed stacking, but these seem to be about the arms, more or less exclusively. I have yet to find anything on fast hands on the internet, and I've been searching for a while. I've seen some people speaking relatively quick sign language on a city bus, so I'm inclined to believe my military friend.
Are there exercises to improve manual dexterity? Anywhere from the wrist to the digits -- how can I get more use from the fast-twitch muscles in my hands?
Bonus points if you can tell me what that military language is, or if he was pulling my leg :P