After seeing Mike and Deeno's amazing star trail images, I thought I would give it a go myself. I was planning to capture around 200 to 250 30 second images but was stopped short by dew forming on the lens.

I decided to pack it in early only capturing around 20 frames.
Stacked in StarTrails.de and processed in PS CS3. Canon 450D, 18-55mm lens at 18mm. ISO 1600.
The reason for the dotty star trails is because I used ICNR darks. I know next time not to use it.
Thanks for looking.