"It was interesting to note that the Canceled Sale quiz responses consisted exclusively of U.S. sales, in keeping (unfortunately) with the general focus of The E-Sylum and The Asylum. Nevertheless, at the risk of boring our 250-strong membership, here's my 2-cents' worth:

Postponed due to the commencement of Desert Storm, Swiss Bank Corporation's Sale #27 of the tremendous Emilio Ortiz collection, originally scheduled for Jan 24, 1991, in Basel, canceled and later held on Sept. 17, 1991 in Zurich. This sale featured (among many other stupendous rarities) the "Rincon 8" which graces in gilt the cover of the Guttag catalog, (and which was also the highlight of Sellschopp's collection - Swiss Bank #20, where auction fever over this coin ended a lifelong friendship and set a price record.) An example of the original (unadulterated) catalog, and the later much rarer edition (with its new date sticker covering the old date) recently sold in Kolbe's sale 79 (lots 622 & 623). Of interest is Kolbe's footnote to lot 623, mentioning the "…Lars Emil Bruun collection of Swedish coins [whose] first component, featuring medieval coins, was sold in May 1914, but the eruption of World War I prevented the second part of the sale, scheduled for October 26 & 27, 1914, from taking place." Seems George already had your contest in mind long before it started!"