Well my favorite blunder is the Mar Climate orbiter where on set of instructions programed were in English and the other in Metric causing the loss of the spacecraft. With the money quote "People sometimes make errors," said Dr. Edward Weiler, NASA's Associate Administrator for Space Science, there in no patch for stupid.

"This report traces the history of some major software projects and identifies the flaws that led to their failure. Could things have been done differently...?"

http://www.scism.lsbu.ac.uk/inmandw//past/9697/projects/prj127.html

True. I really wonder why any scientist worth its salt would use anything other than the metric system, though...

I did a quick search and found this which I used to colour the above article..some good stuff in here: http://infotech.fanshawec.ca/gsantor/Computing/FamousBugs.htm