The latest HRSC upload (June '11) contain some pretty incredible dust storm images. I've put together a few colour animated gifs to see the movements of the storms and associated dust devils.
The gifs are all here (BTW Picassa doesn't seem to like them being animated so you might need to download them to see the movement).
This one is a particular favourite.
Click to view attachment
There is a little chromatic smearing as there was movement within the RGB images but I think the overall effect is pretty nice.