The reason I am buying and not making is because my father had an extra cigarette lighter from a car hanging around (will post pic later) and I am a DIY junkie.
Anyways I see this picure of one from engadget by sunbeamtech
[img]http://www.weblogsinc.com/common/images/5067532430807276.JPG?0.903791693550578[/img]
and I realize hey I can make one of those
So... is there anything special I have to take into consideration (power wise)
I figure one wire to power and other to ground, theirs uses a 4 pin but could I use a 3 pin (fan connector?)
what wire should I use? blacks for ground and what is for power?

iirc those run on 12v. Though I wouldn't suggest doing it, for two reasons. It'll add heat to the case and perhaps be a fire hazard when used. And the more important one is that if you smoke near your computer the smoke will gum up the bearings in the fans something nasty and coat the pcb's with goo and it's just not good.

It's not for smoking but for charging things, using satellite radio without home kit, etc.
It's not like an actual cigarette lighter but it's a 12v outlet.

Should work fine for that. Only other thing I can think of is make sure to check out how many amps what your pluging in draws cause I think some of that stuff eat quite a bit.

how many amps would the connection supply?

Depends on what PSU you're using and what else you have drawing from that particular 12v rail.

Keep in mind though that it'll try to supply as much power is demanded from whatever you plug into it (and then shut off if it needs to), so don't go plugging in one of those drills for taking lugnuts off or an air compressor.

It'd probably be best to look up the draw on whatever devices you plan on using with it first.

Zactly what I was saying. You should be able to do low draw things like charge a cell phone (I think that uses like 2a or something. But anything rather demanding will cause your psu to switch off.

Since it is a computer, and there are only so many things you could get into the house with... You should be able say charge a cell as I said. But you mentioned one of those satalite radio's... Now that should work if it doesn't have an amp or anything in it. With an amp the current draw would be huge. But I don't think they do so that should work fine.

Just check your devices and then figure out what rail on the psu your going to be using and how much draw is already on it and you should have how much you have available and can then see which of the devices you can run.

However there is always the chance of catastropic failure (Think MythBusters) so in the unlikely event that something bad does happen, I warned you so don't try and blame me! <.< >.> But in all honesty, I can't see what would cause a problem other than overloading it.

I'm going to stop rambling now, I'm bored and this is a fairly interesting thing to me

And to answer what is for power, that would be the yellow. Yellow is 12v, red should be 5 and orange 3.3v. But I could have reversed them as I usually do. Make sure you let us know how it turns out.

You could use like a 4A fuse to prevent the PSU from dieing.Or if you have a better idea... or are better in electronics you could use some protection with transistors.

Nah, orange is 3.3v and red is 5v.

part 1 of cigarette lighter bay is done
picture

now I gotta wire and hook it up!

I'll second throwing a fuse inline.