PSU

Ok, I am making a unit, that will contain my pi, A powered usb hub (converted from a cheap standard one), a keyboard/mouse combo and a screen, all in the one unit.

However, I really dont want to have to have 3 power cables trailing out of it. So what i want to know is how easy would it be to get/make a power PSU, so i can just have the one cable, and internally it powers everything?

any advice? or even just some pointers to get me started?

Additional information.

3 required outputs are:
Screen - 12v DC
USB hub - 5v
and pi - 5v

Not sure on amps for the first 2, but the pi needs to be atleast 700 mA

for all 3 i have wires with exposed ends, that i can either solder straight onto a board, or I can attach to a plug.

Still searching for answers :/

I have parts on order to do something similar. I will have a toggle switch on the front of my chassis so I can select my 12V source to be either from a small sealed lead acid battery or a switching power supply. I am converting the 12V to 5V with a car cigarette lighter adapter from mediabridge; you could also use a DC to DC convertor. The adapter accepts 12V on its input and has two 5v outputs, one at 2.1 amps and the other at 1 amp. I will be using one of the outputs to power the pi and the other to power the coils of my 8 channel relay bank. You really need to know the power requirements of all your devices to make sure that your 12V source and the 5V outputs can handle the load.

Hi Dan, sounds like my original goal (have since decided against a hard drive) I'm too lazy to write it all again so check out this link http://forum.stmlabs.com/showthread.php?tid=3918 Specifically the last halt of the post.

I've done something similar with my 'PiSU'
It uses the IEC power plug, wired into a 5v switch mode power supply which I've then wired to the Pi and Hub.
Dealextreme have both a 12v and 5v switch mode power supply available which could do what you need to do.

I've started work using a 12 v mains addaptor which plugs into this
I then take one feed for my 12v screen, and one feed into this to get 2 5v feeds for my pi and hub. I wanted all 4 ports on my hub, otherwise i'd have powerd my pi from the hub too.