Looking at our own archives (I remember it well):

Date: Thu May 15 00:02:46 EDT 1997
Subject: A.Word.A.Day--floccinaucinihilipilification
X-Bonus: I think there is a world market for maybe five computers. -Thomas Watson, chairman of IBM, 1958

floccinaucinihilipilification humorous. [f. L. flocci, nauci, nihili, pili words signifying `at a small price' or `at nothing' enumerated in a well-known rule of the Eton Latin Grammar + -fication] The action or habit of estimating as worthless.

1829 SCOTT Jrnl. 18 Mar., They must be taken with an air of contempt, a floccipaucinihilipilification [sic, here and in two other places] of all that can gratify the outward man.

Apparently Scott used it three times but I've not found the other two yet. I have used it approximately 0 times.