> What's a good way for a PIC to control (on/off) a crockpot?
> (120 VAC, a couple hundred watts.)

Dear scaredy-cat Michael ;-)

I'm afraid you're going to have to come to terms with some voltages
with a lot more ooomph behind them than a 78L05

The PIC will be a timer ?

First thing you have to sort out is the power supply. Something
along the lines of this

http://home.clear.net.nz/pages/joecolquitt/txlesspsu.gif

Unless you want to go with a transformer/plugpack. Which sounds
like you'd be more comfortable doing. And a lot less dangerous too

A transformerless supply has the possible advantage that it might be
physically smaller and can be installed inside the equipment. Although
your PSU load is fairly low, so you should be able to use a quite
small transformer

A relay isn't a bad idea, even if it does arc a little (there are ways
to minimise or eliminate that anyway). But relay coils need power,
a few 10s of mA, so the PSU has to be up to that. As a rough
guide, 1uF at 50Hz will "pass" about 70mA. The 0u68 capacitor
in the diagram -> 0.68 * 70mA = 48mA. But you put in whatever
you need to get the current required

One alternative to a relay is an opto-triac / switching triac combo.
The opto-triac isolates the PIC from the high voltage and also
provides drive for the main switching triac. eg the r-h side of

http://home.clear.net.nz/pages/joecolquitt/ir-rec.gif

The load is your element. As it's resistive, I'd not expect any
of the problems you have with something inductive like a
motor. If the opto is a zero-crossing type, eg MOC3041,
that would be better, but may not be necessary

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