Mine does it. I've noticed talk on this board in the past about it too... You can feel it but it isn't huge... Think about how much a regular ICE shakes at ignition though... I'm sure the Prius barely compares... 
adamtraidman said:Just got my #9 2004 a week ago. I'm curious if everyone experiences the slight tremor / vibration when the ICE starts up and shuts down. How much vibration is typical? I know it's a rather subjective measurement, but sometimes I notice the care shakes a bit when stopped at a light and the ICE presumably is turned off.
Adam