I wish I knew how to do this. It probably would not work with my camera. I have a Canon Powershot S3 IS. Anyway, great picture.

willij, the key is to be able to open your shutter for a timed release. You will also need a tripod or something to set your camera on while you take the photo. This photo was a three second exposure. I was shooting at 100 iso. You can either use the timer function on your camera or use a cable release to fire the photo. This way the camera doesn't move when you open the shutter.

I'm not sure if your Powershot allows for timed exposures or not, but if so you could do this pretty easily.

willij, your camera supports shutter speeds as slow as 15 seconds, which will allow you to take a picture such as the one above. Just fiddle around with your settings and see in which menu this option is hidden.
BTW, I've was able to take a similar photo with an entry-level digicam, nothing nearly as sophisticated as an S3 IS. Check it out here: http://beta.zooomr.com/photos/41387@Z01/909623
Cheers.

Thanks. I will try that.

Great photo! I must try one of these!