I first learned about the Ariane 5 explosion, partly caused by reusing Ariane 4 code, around five years ago at a one day taste of YoW! 2012 in Sydney, where I was also introduced to Don Reinertsen’s Keynote on the Practical Science of Batch Size (unfortunately it looks like the Melbourne copy of that video is not currently available, hopefully it comes back sometime).
In any case, still my favorite bug:
Follow up 16 Nov 2017 – It’s come to my attention that Bugsnag agrees too. Good on them!