On one of my boards we had a guy who was a MM back in the mid to late eighties. He pretty much explained how things worked, but did say a lot has changed since that time. I wish I could find that.
Another stock that I still own had a very nice run several months ago. As far as I can tell, the MMs just sat and watched. But yeah, I'm sure they sold, too, and picked up some when it hit the bottom. At this point, months later, I think they are a bit short on shares.
News 
Market Data 
Discover 
