Hi Nextman,
You actually found a bug in Open Site Explorer that we are in the process of fixing. Binary files are mistakenly being counted as links. It's a known problem and is already being reduced, but you'll still see some of these for the next couple of months. Here's what Rand has to say about it as part of his larger post about the Linkscape Update.
http://www.seomoz.org/blog/november-2011-linkscape-update
As I noted in the September index update, we have had some serious issues when crawling deeper on large domains and encountering binary files that contain code our crawler recognizes and treats as a link. To help stop this problem, we applied a black list to this index to stop a large number of the files folks had reported to us (our estimate is that ~40% of binary files are now removed). However, we know there's still more than a few of these in the database of links so we'll continue cranking away on solutions to remove them all. Our hope is to have them reduced in the next index (November) and nearly eliminated by the December index. If you're ever curious about the next/previous updates, you can always see data for them on our Linkscape calendar.