Stopped by the local brick-n-mortar toy store today just to see what was up. They tossed me this: Said someone left it (Nikkor 200/4 Ai) under the seat of their truck for 3 years. Brought it in to see if it was worth fixing, and Nikon said how much it would be. He said, "Forget it!" and wanted to toss it. So they kept it and waited for me to darken their door. What the heck, I thought! It's a free lens! It's at least worth trying to clean it up. These old lenses aren't that difficult to disassemble. So tonight, after supper, I cracked out the tools. Other than the dust on the front element, there was a lot of fungus on the rear of the second element. A couple rounds of scrubbing cleaned that up nicely! But more trouble lurked further in. But still within reach of going in through where the aperture blades are. Several q-tips and some cleaning fluid later; Reassemble, and I get a rather nice 200mm Ai out of the deal. Yes, there's still some fungus further in, but not on the glass. And there is a slight amount between the front two elements. But heck. It's free! I'll need to get a spanner wrench to take off the retaining ring between the front two elements, but that can easily wait for now. Now to take 'er out and shoot 'er (as opposed to it's fate as of this morning, and that was landfill fodder!) I love saving old glass!