>..I still remember from my schooldays a sentence composed of a word used ten
>times in succession ..

Paul: I think it is one of those puzzles that one knows if one knows it (what is happening to me - Deolali?) - but I think the sentence will be of a word that can be a noun - subject and object, verb, adverb and adjective. Maybe the answer is in finding out which word can be all the parts of the speech.

Meta: "Post posters' posts, a poster posts posts, post posting posts".