I blew a 100/80w bulb in one of my headlights the other day.  I had to
check in on about 6 auto parts stores (in the NYC area) before I could find
one that would even order a replacement for me.   If anyone has H4s I would
recommend getting a spare bulb or two.  It seems like the 100/80s are
particularly rare, at least around here. 
 
Evan Estern  
evestern@pipeline.com