One of the nice side benefits of taking star trails using the stacking action is you can make a timelapse out of the shots. Here I used the "Comet" mode of the Advanced Stacker PLUS and created the timelapse using Picasa 3. I have a heap of Adobe products that could create the timelapse, but Picasa 3 is so darn easy (and it's free).
See the single shot created from this sequence here: flickr.com/photos/steventheamusing/10103485165
Music is "Janalang" from iStockAudio. This was a free download selection of the month.