Before I started on building Bog's Paddleducks engine, I built this LED lamp for my wife's workshop (she does girly things there that I just dont understand)

Basically it is a high powered LED light ( or 3 lights

)
I built it because the lamp that my dearly beloved used to use was a standard 2 x 60watt lamp and she found it would get unbearably hot to work near, and the flicker that flourescent's give off gives her headaches. The solution? LED lamps, they run cooler than conventional incandescent bulbs and use far less power.
Here's a closer shot of the Light module. They are held onto the main stem via a little ball and socket arrangement. Then there is a little knurled thumbwheel that clamp and releases the grip on the main stem.

And the shelf clamp, the design comes from a clamp that I saw on Arc Euro's website that is a vice stop ( I think )

The light bodies are made out of Ali' and are 2 piece in construction.

The LED sits against the piece on the right, the LED has a disc of aluminium on the back of it as a slight heatsink, I say slight because it needs additional heatsinking. Hence I use the back piece as a heatsink and I finned it for additional cooling.

As you can see the two halves are a push fit, they stick together quite well, plus when the LED heats up and then the heat transfers to the back part, the heat will expand it ever so slightly and jam tighter. (well that's the theory anyway).
The light from these LED's is usually very narrow, but very intense in beam. That's why you need a diffusing lens, that little clear plastic thing on the left of the above photo.
The LED's need 3.2-4.2 volts each at about 400-650mA (depending on how bright you want them) I got a little power supply from the same place I got the LED's from which powers them all and it fits inside this,

That is a standard inline light switch got from B&Q. I had to clear out some of the plastic innerds including one of the screws holding the 2 halves together, hence the cable tie for added peace of mind.
So how does it compare to a normal light bulb? I did a little test. I got the old 60 watt lamp, adjusted it to the same height as the LED's and switched both the LED light on and one 60watt bulb on.

As you can see, I am not using flash on that picture as my flash is the test subject!! I have set my camera on Manual exposure and these next 2 shots were both taken with the same settings, no adjustment to either exposure or to colour temp settings, and also absolutely no adjustments made on the computer in photoshop.
1st up is lit only by the 60Watt lamp.

2nd is lit only by the LED lamp.

Now let me tell you that each of those LED's are rated at 3watts, so a total of 9Watts of power being drawn

I got all the LED's, diffusers and the power supply from Dealextreme in hong kong, these are the links;
LED's :
http://www.dealextreme.com/details.dx/sku.1302Diffusers :
http://www.dealextreme.com/details.dx/sku.2395Power supply :
http://www.dealextreme.com/details.dx/sku.14034Tim