> A relay likely won't work very long, if at all, under that kind of
> use.  So, I need a transistor of some sort, right?  Probably PNP,

> to set something up like a Darlington pair

Danny, this would be similar to one side of the high-side of an
H-bridge. The 5V control (from the PIC presumably) goes to
the base of an NPN, which in turn controls the base of the PNP
high-current switch in the +ve. The NPN not only isolates the
PIC from the 12V on the PNP base, but also amplifies the PIC's
pin current. The bulb hot goes to C and cold side to 0V

Like Fig1

http://instruct1.cit.cornell.edu/courses/ee476/FinalProjects/s1999/bell/abel
l.cnazarian.ee476.finalproject.rccar.html

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