> Keep in mind that the ideal design may have little meaning for the
> application intended. 100,000 hour life of leds for use in flashlights
> for example. How many sets of batteries would you need before you
> approached the 100,000 hours of the bulb?

Also, these "lifes" are statistical averages--like "mean time
to failure" for disk drives.  I bought a 36 LED light for the
Mountain Club cabin:
http://store.sundancesolar.com/12v36ledbudi.html
which has an advertised "approx 60,000-hour life" and it
started failing very quickly--a few LEDs out, then more,
then more.  When I sent it back ~1/2 of the LEDs were out
or flickering.  Granted, this was not a single LED, but
more complex.

Maybe they are not "statistical averages" but "statistical
predictions"....

Richard