In regards to self fulfilling prophecies:
The phone companies won't admit it but they are scared that at 1 second
past midnight, everyone will say to themselves, "Hmmm, lights are still on,
I wonder if the phones have stopped working?" and then within 1 minute,
millions of people will be lifting their phones off the hooks to check
dial-tone. You know what happens when that happens. 
-Hank
As Alan points out, it looks like silly season will be in full swing. Here
is a site claiming it will check the top web sites in the world, and if 5%
aren't responding at 1 minute before midnight (pick your time zone) a major
disaster has happened.Yahoo Finance - Stock Market Live, Quotes, Business & Finance News
As has been pointed out before, many sites plan to shutdown their web
sites or
disconnect from the Internet over the New Year's weekend. Which I guess is
a self-fulling prediction. The Internet is still considered an "extra" and
not a necessary connection like the telephone or ATM. I haven't heard anyone
suggesting they would turn off their ATMs, even though they are Y2K ready,
just