re: Millenium Bug
3 memorable incidents which happened in the runup to that (memorable as in they happened to me):
1: A lot of NTP systems crashing in February 1999 as the seconds since january 1 1970 exceeded 2^31 +1, including every Allied Telesyn router using NTP and virtually the entire Internet in China going titsup for 24 hours as a result.
2: A lot of security systems discovered to lock up if the clock advanced to 9/9/99 (which was regarded as a test date) and stayed locked up forevermore.
3: The complete brainscrambling of the Palmerston North NEAX61E telephone switches (80,000+ lines plus national call switching) thanks to memory corruption which was only exposed when y2k software was loaded in and the switches rebooted. To compound it, that scrambled crap had been written to the backup tapes for 18 months or more with the only clean backup discovered being 24 months old - The entire area had no dialtone for 18 hours and restoration of the backup plus replay of all the changes made since that point took in excess of 6 weeks.