Inside a generic LED disco pinspot.

I added this LED pinspot to an order while I was buying some stuff on ebay, just to take a look at it. It was described as being a 240V unit with a 3-5W LED and had the cryptic advice that I would need to add my own plug.
It arrived with the box marked as being for 12V DC at 2A and had two beefy wires coming out of it, one red and one black.
I played safe and hooked it up to 12V DC and nothing happened. An internal examination revealed that it had a mini switching power supply (most likely a generic 3W one), so I decided to give it a go on 240V. It worked on 240V although once again the back metal housing is completely unearthed and I don't trust any of these mini supplies to have proper isolation from the mains due to the choices of components, clearance and the way the transformers are often would with the secondary straight on top of the primary.
It does produce a decent narrow beam with a square image of the chip being projected quite a distance. The power consumption is less than 3W which is normal for a lower voltage red LED (2-2.5v) on a typical 3W power supply designed for white LED lights (3V).

The alignment of the LED is not quite perfect. There are screw holes for clamping down the star-style LED, but it is stuck down with thermally conductive silicone instead. The collimating lens in front of the LED is stuck in place with soft silicone-like goo and the front lens is clipped in with a metal ring if I remember correctly.
All in all, it would actually work well with a modest throw in a dark nightclub environment, and the heatsink is more than enough to allow continuous operation. The lack of an earth and indeed a proper flex is annoying, but not critical as long as the light was clamped onto a grounded truss.
The back heatsink housing is all aluminium alloy and the front section is plastic. It looks quite hackable for different colour LEDs.