PDP-11 price guides

Has anyone worked on, or thought about working on, a "price guide" specifically for PDP-11 (or PDP-8, or VAX) hardware? I know of Michael Nadeu's book for microcomputers (which I keep meaning to buy), but this is really a different realm of things, as you can configure (for example) a PDP-11/23 in a whole lot more ways than you could with a C-64. I've thought "hmm, this would really be handy" a few times before, but haven't had much time to sit down and work on it. It'd be nice if I could keep it up to date, and use multiple data sources (not just past marketplace.vintage.org sales), including eBay and semi-private sales. Also, a "rarity" quantity of some sort would be useful, and could just be "very rare" for, say, the preverbial 11/74 (the one that's supposedly 2 CPUs), to "common" for an 11/23. Thoughts? Pat -- Purdue University ITAP/RCS --- http://www.itap.purdue.edu/rcs/ The Computer Refuge --- http://computer-refuge.org