(Sorry Chris L, I was distracted. It must have been the music that made me lose track of the fact that this was a post before post 1000. Yeah, that's it.)
I don't do any formal meditation at all - no zen, no yoga, etc. Biking through the streets of Chicago is probably the closest I come to meditation, as I have to keep my awareness open constantly. In Zen meditation, if the pupil gets distracted, the master might hit the pupil with a stick. When I'm cycling, if I get distracted, I might get doored. Or fail to notice a sudden swerve that a taxi is making to pick up a fair. Etc.
There's a zen koan where three pupils complain to their master that they haven't yet found enlightenment. The master said to meditate one day more and that if they hadn't found enlightenment, they should kill themselves. The next day, they all found enlightenment. In a similar vein, I know that if I don't maintain my awareness, I know that I could kill myself (in a stupid accident.)