To those of you who responded with humor, thanks for some good laughs.
At least, I thought it was humor... BTW, Joe, I am sure you realize that
calendar / scheduling software will let us look at leap days, too,
although some people might not find that as persuasive as store bought
hard copy.

Back when the YEAR2000.com's mailing list was free, there was serious
discussion about, not only whether it was necessary to code for 2100 not
being a leap year, but whether it was necessary to code for 4000 not
being a leap year. It was only after a message on this list sent me to
the National Bureau of Standards web site did I learn that 4000 is a
leap year... oops. All the involved explanation I had read about
millennial years was hokum.

Last leap year, I emailed the MIS staff at my then current and now
former employer, asking if there had been any problems the previous leap
year. I was assured that there was no problem. Leap day morning, the
early birds were flying in formation, trying to correct an obstinate
data entry screen that didn't like 022996. Then one of the programmers
seemed to remember going through that very thing four years before.

I also read about a DMV that used Julian days. When their software would
not even come up on 96366, they closed for the day. That's a bug I could
live with...