If you've had beers with a few programmers, sometimes the conversation gets around to a one-ups-manship game of who's faced the worst bug. One story I retold just the other day was about the IT department that was truncating long running connections at the firewall for security. Silly programmers, we had written our applications to assume that a TCP/IP connection could last as long as the application needed it to last. While it didn't take long to discover the bug, it did take weeks to clean it up - policy decision are the hardest to change. Policy is not software - it is ink & paper signed in blood-ware. Much harder that hardware. Capable of withstanding krypton drills and sharks with frigin laser beams.
"One of the primary programmers for the Mark I was a woman, Grace Hopper. Hopper found the first computer "bug": a dead moth that had gotten into the Mark I and whose wings were blocking the reading of the holes in the paper tape. The word "bug" had been used to describe a defect since at least 1889 but Hopper is credited with coining the word "debugging" to describe the work to eliminate program faults."
-- John Kopplin - An Illustrated History of Computers