Ok, this is embarrassing.
It seems that whatever you were looking for has gone 404 (that’s techspeak for “I swear I put it just there, and yet I can’t find it anymore”).
The most probable reason is that the content was removed during a website rehaul – possibly because it had become obsolete, or too unwieldy to manage. That’s the case with the former 1,500-plus curated weblinks collection, for example.
Other causes are… Oh, well: I must have bungled something up, all right? It happens even to the best, and you have over one darn thousand other pages, articles and whatnots to read on this website anyway! There’s no need to make me feel guilty for that, right?