We were looking for a cheap corporate videoconferencing solution that would allow us to share whiteboard, and even projected screens, in regular lighting conditions.
We knew that Apple's discontinued iSight webcam was good enough, but it's, you know, discontinued. In any case, we don't have Macs at the office (yet). We knew from recent research and past experience that no other consumer grade webcam would work. We also knew that firewire based camcorders (digital video cameras) had been known to work with OS X iChat AV and on XP wiht help from 3rd party software, but I thought firewire camcorders were extinct. USB camcorders, for unclear reasons, don't seem to have the ability to act as a webcam on XP, though there's some software that claims to support them on OS X.
I spent some time on Google and Amazon looking for a firewire consumer camcorder, but all the pages I found were old, and many of those were in decline. None of the camcorders they mentioned are sold now. I searched on Canon's web site and on Amazon, but I couldn't find anything. Even now that I know the Canon ZR 850 has what I need, I still can't find that information on the Canon website.
So a colleague asked at the Roseville Minnesota National Camera office. An expert there thought we had two choices, but he recommended a hands-on test.
We tested onsite with my MacBook and we found both of the old-fashioned camcorders worked with iChat AV. Next we'll buy one and test in an XP box with a firewire card and some XP add-on software. If it works we'll buy a few cameras for the team. We'll pay a premium for the cameras, but it's just payment for help we got -- and its corporate money.
Which brings me to the moral of the story. Even in these days, there are some seemingly easy questions Google can't answer. This wasn't a question about cancer therapy, all we needed to learn was if there were any firewire consumer camcorders left on the market. That seemingly simple question required a human expert  to answer.
 I now realize I probably could have asked in Apple's iChat AV forum, but we were thinking XP, not Mac. Even then, of course, we'd be relying on a human expert.