Yeah, if it weren't for him, that thread would be rockin'.
Someone did make a good point that maybe it wasn't the flat part that was exposed...if the blade contacted the outer edge of the sphere, I could see how it'd maybe flex around it. Still a one in a million shot though. If a sawmill blade tried to go straight through that thing it'd probably ruin some millworker's day.
I love weird stuff like this, where you come across something uncommon with a strange chain of events behind it. Years ago I made a few unsuccessful attempts at keeping a 'blog' going, and here's one entry that I liked:
http://chronicnerd.blogspot.com/2004/11/midnight-in-military-ruins.html
You might be one of the few people on earth who'd appreciate what I was trying to get at there.