I've just completed a rather tedious (but enjoyable) trawl through this Forum up to the end of 2012, and had a clear-out of defunct threads. Most of these fell into several categories: eBay sales listed, where the product was long gone; privately sold items, also long gone; and commercial products where the manufacturer or dealer has closed and the item is no longer available. Another category was posts with completely missing photos, or links that now lead to nowhere. There were also a number of threads that were mis-categorized, and these were moved to the correct Forum.
You'll note the threads I have completed are all prefaced with an (M) -- for "Manufacturer, Maker, Material" -- in the title. With any luck, these threads are still useful, and of value to current and future members looking for information. I can't vouch for all the links, so if you find one that is no longer relevant or working, make a comment in that thread stating what is wrong -- it'll then pop to the top of the forum -- and I'll have a go at fixing it.
One more thing. If you offer a private item "for sale", and it eventually sells, please note this in an update in the original thread. These can then be deleted as being 'closed sales'.
I'm spending the year dead for tax purposes!