Variable temperature controlled soldering stations are overpriced, plain and simple. I'll bet there are plenty of casemodding n00bs out there who have blown up one blue led too many, and are looking for a cheaper way to reduce the heat of their $5 30W soldering iron. Holy crap an introduction on Afrotech that didn't mention porn? That's just wrong. Porn porn porn p0rn pr0n sweet sexy soldering iron porn. Ok thats better. On with the guide.
Stuff you need from Home Depot:
Wall outlet - $0.38
Lamp dimmer - $4.89
Faceplate - $1.47
Box - a buck
A soldering iron if you don't already have one.
From junked power supply in CMU dumpster:
Power cord
Itty bitty LED
ARNOLD sized (1 watt) 15k resistor. (For ppl in 220v countries use a 30k resistor).
If you can't get a 1W resistor, make one out of a bunch of series and parallel
resistors. You will know your resistor was too small when things catch fire.

<Insert standard bullshit about how playing with mains electricity is so dangerous that it will kill you, your children, your favourite out of work 80s sitcom star, and possibly give you an acne problem if you even breathe on an electrical outlet>
Basically what you do is use a lamp dimmer to vary the voltage going to the soldering iron. And an optional LED will tell you whether the thing is on or not.Cut off the end of the power cord, and figure out which
wires are live, neutral, ground. It seems to be standard that black is live,
white is neutral, green is ground, but just in case heres how you can safely
check which is live- Set your multimeter to its highest AC voltage measurement
setting. Separate all 3 bare wires a good amount. Connect one multimeter lead
to the wire you want to test, and the other lead to your finger. Then plug in
the power cord. The ground and neutral wires should give an almost 0 reading,
and the live wire should be significantly higher. Since I was standing on a
carpeted, wooden floor I only got a readout of 35V, but between live and neutral
there was the normal 110V.

Unplug the cord and thread it through your box. Use assloads
of solder to firmly fix the ground wire to the ground plate of the wall outlet.
Do the same with the neutral wire, and the neutral side of the outlet, which
should be clearly labelled. Solder the lamp dimmer's green wire to the same
point where you connected your ground wire. Then take one of the dimmer's black
wires, and solder it to the power cord's live wire. Cover the soldering job
with electrician's tape or something. Take the dimmer's other black wire and
solder it to the live side of the wall outlet.
Use your miniscule penis to poke out a little hole in
the faceplate let the LED through. Solder your resistor to one end of the LED.
Solder on a little wire connecting the 'dimmed' live output to the resistor.
Stick the dimmer onto the faceplate, and then solder the bare end of the LED
onto the ground plate of the dimmer. Throw some glue and insulation in there.
So now you should be able to trace a current path, live from mains->dimmer->
resistor -> LED -> ground.
Screwed anything up yet? Ok. Now screw everything up.

For the final professional touch, stick a dremel in a
vice and sand down the tip of your soldering iron to a sharp point, so you can
fake that you've got one of those $20 surface mount tips. Mine is so sharp now
that I could probably do a pyrographic tattoo with it. Hmm.. hey Infowar wanna
try that out?
Plug your box into the wall, and plug in a soldering iron in, and play with
the dimmer, and see how the voltage/LED brightness/iron temperature changes.
And um... thats it.

Ok that wasn't very entertaining was it. Umm.. ok so when in doubt.. break out
a cliché. Cat!