Knoppix was basically the dawn of mass-market Linux, and I think it goes unsung. Installing Linux on a fresh computer, or even worse setting up dual boot, was way too much of a commitment to try it out. Knoppix gave us live CDs, and everybody who had been making excuses for years could test drive to their hearts content and find out it wasn't so hard.

It was certainly my Linux start. I'd been embarrassingly defying friends for years and sticking to Windows because I'm a creature of habit - thank god I jumped ship before Vista, when all my habits would have changed by force.

I think the 1-2 punch of Knoppix and Vista might be responsible for a significant portion of current Linux usage, at least in a Butterfly Effect way. People who were trying out Linux when Vista came had an easy escape hatch, and wouldn't have felt any urge to turn back until Windows had reverted to usable again.