I was a consultant at the Texaco refinery in Wilmington, California (near Long Beach) in the late 80's, and the Los Angeles "Air Quality Management District" folks mandated that they decrease the average number of cars going in and out of the main gate per month in an effort to improve the air quality in the LA basin. Not sure how that would have compared to, say, decreasing the smoke-stack emissions at the refinery, but I'll leave that for YASP. (Yet Another Slashdot Post) Anyway, their creative solution was to request everyone at the refinery, office staff as well as the operations guys, to work "nine nines" and they'd get every other friday off. This ended up working extremely well for everyone that did it, and it did not seem to have any negative impacts at the refinery, so... I'd say it was a success 20 years ago. I have no idea if they are still doing that. I guess if they had gotten everyone in LA to adopt this plan it would have reduced smog caused by car emissions by roughly 10%. I never heard of anybody else doing this, and we now know that smog caused by cars is a much smaller percentage than was once thought, so how much did this help the smog situation? I'd say it was bureaucrats wanting to look like they were doing something about a problem.