Since I'm down to only a few hundred useful things that I need to get
done at home, I though it'd be entertaining to make the taillights on
my Caprice light sequentially.  But really, a simple R/C time delay
seems boring, whereas the ability to make the 3 bulbs flash in amusing
patterns is interesting.  Off-road, of course - I'm not sure if it's
legal or not to do anything like that on the road, but I don't want
some boob ramming the back of my car due to screwy brake lights either
way.

So presume that I'm capable of determining whether or not the light
is being activated by the brake or a turn signal, and whether or not
the car's in drive.  In fact, presume that I've got everything figured
out but how to actually control a few bulbs.  I guess that using a
PWM-like "turn them on and off real fast" thing will work fine for
making the lights appear to fade in and out.  The bright side of an
1157 should be on the order of 25-30 watts, which means I have to
switch about 2.5 amps at 12 volts.  I need individual bulb control,
and there are 6 or 8 bulbs, depending on how ambitiously I try to kill
my time.

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,
since I can't really interrupt the negative side and therefore have to
switch the positive lead?  Basically, I don't know jack about how to
select an appropriate transistor for this application or what to look
for other than current rating.  Do I need a particular type, do I have
to set something up like a Darlington pair, does that even make sense,
etc?  I'm pretty sure that all I have is enough knowledge to make me
sound stupid to those who know in this area, so I'd appreciate both
general knowledge and specific part numbers. :)

Thanks!
--Danny
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