Gary had an interesting thing happen at work. Of course, since it happened to Gary it was OUTRAGEOUS! and UNBELIEVABLE! and CAN YOU BELIEVE IT? But I felt it was pretty interesting, even without the extra glaze of Gary on top.
Gary had a Y2K +10 problem. Remember Y2K? When I had to spend New Year's alone because my husband had to gently shepherd his Hewlett-Packard robot girlfriend into the new millennium? Well! Come to find out SOME programmers were slackers and did not test for all the other potential Y2K-like date issues, including the ones that might pop up in 2010. (Not Gary, of course, he's probably tested everything out to 12/31/9999 and even to the rollover on 01/01/10000.)
So, if your computer began acting wonky on 01/01/2010, you might be in the same situation as Gary and these German ATM users.
If your PC did not wonk, you can go to this fine site to find every other significant date, why it's significant in computer math, and what to fear.
For example, I remember learning (and using) the algorithm that states that if a year is divisible by 4, it's a leap year. Well, that handy rule works great from 1900 to 2100, when it seems there's supposed to be a leap day, a February 29, and I can tell you I know of one Excel spreadsheet that's going to crap out on that day. (And if you've ever played with the Julian dates in Excel, know that Dec 21, 27374357 is 10,000,000,000, or Julian date ten billion.)
The list doesn't mention 2525 (if man is still alive), but it mentions that the Jewish Y6K happens on September 29, 2239, at sunset. If we make it past the Mayan end times on Dec 21, 2012, then set your TiVos for Oct 13, 3173, when there is "Another Mayan Long Count end; world re-created."
If you've got geek, go geek out on that link.