Walking around yesterday (in the north SF bay area), I came across some
really nice looking pepper plants in a front yard -- probably at least
four feet high. The peppers were maybe 2 1/2 inches long, thin like
cayenne or tabasco peppers, with the pointy end up (stem down), and all
the fruit were completely black.

Just then, the homeowner came outside, so I asked him what kind of
peppers they were. "Diablo".

Well, I love peppers, so when I got home I googled for diablo pepper.
The descriptions and photos all showed red, not black, fruit, which was
hanging pointy end down.

So what kind of pepper did this guy have in his front yard? Clearly they
were being grown for culinary, not decorative, purposes.

FWIW, I have a strong suspicion that the homeowner's first language was
Spanish, not English -- not that this matters in any way except that
there may have been an error in translation.

Isaac