Just a short star trails image of an Iridium flare. I didn't actually know it was going to occur, catching it on camera was a complete fluke - I had the camera set up just doing some time lapse stuff.
Taken with a Canon 400D. I was taking continuous 30 second exposures at ISO1600. I used the Startrails program to stack a dozen or so images together. I also edited the image slightly to remove the gaps in the Iridium trail that resulted from the short time between images.