Like many folks, I'm a refugee from a failed dotcom, in this case, one with an active alumni list of folks trying to help each other find jobs. A guy on that list just forwarded me the URL for the coolest new networking site: Eliyon's CorporateAlumni. I think it's still in beta, but it's worth looking into if you're interested in tracking alumni of various companies to their new jobs. Right now, it tracks 15 million business people.
You type in a company name, and it tells you who works (or once worked) there, with links to information about where they might have gone. You can also search by function. A great way to find old colleagues, or to figure out who, say, the marketing person is at a company where you'd like to work. A boon for job seekers!