I make no claims about the effectiveness of the technique. Anyone have first-hand experience?
For one, it is an excellent way to hone the practice of focusing your mind on your immediate activity. In Buddhist mindfulness practice you will focus your mind not just while sitting meditation, but also while walking or doing chores. Eventually you will be able to bring this focus to every activity you engage in during the day.
So in a way you move into the zone on a semi-permanent (or even permanent) basis.
The broader Buddhist philosophy is also an excellent way to eliminate distractions from your mind. In that philosophy, thoughts and feelings arise almost exclusively due to internal processes, and an important aspect of mindfulness meditation is letting those same thoughts and feelings go. So instead of distracting you like normal, the thoughts and feelings will "run their course" and dissipate much more quickly.
This is how the practice has benefited me the most. I now know that my normal distractions (e.g. checking HN compulsively) are not going to provide anything for me -- they are not a source of happiness or contentment. The mindful focus is my source of that happiness and thus preserving it is what I naturally want to do.
All that said my practice is far from perfect, as I do find myself here reading and answering questions. YMMV :)
I've been doing zazen for a little less than a month. Zazen is a little different from vipassana(with wich i have even less experience than with zazen, as i said, less than a month). I chose zazen mainly because it sounds so simple: sit with your spine straight up(in the lottos position if possible, im not there yet, im too inflexible) breathe normally and count your breaths for 10 minutes every day, no magic Indian mysticism involved, which is what threw me off Buddhism the first time i encountered it.