Time affected header images

Sep 8, 2010 at 4:35 PM

I used to have an picture that changed relating to time, now I haven't seen this done with asp.net and was wondering if anyone has found a way of changing a image based on a) time of day (maybe 3 images) b) season (obviously 4) any thoughts appreciated I used to do this in javascript but am aware that the headers are all css driven so thought oh i will ask