Paul [1ponders] beat me to it by a couple of days.
Here is my effort at animating Neptune as it crosses the sky. This is a sequence of 3 images taken roughly a week apart (20/7/06, 26/7/06, 3/8/06).
Each image is a stack of 6 images using Registax (64 sec, ISO400, f5.6). Fancy overlays and boxes added with Photoshop and Paint. ADGif used to create the animated gif.
[Ignore this paragraph now] Unfortunately to keep it under the 150k size limit I had to shrink it down a lot and convert it to greyscale. It just doesn't look quite as nice as the original which was 800x600 and colour.
[Update: Worked out how to keep the image size large now. Image swapped for the full size colour version
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