Thanks also. My favorite (naturally) has got to be the one called stair-stepped mounds in Meridiani Planum, here.
http://hirise.lpl.arizona.edu/PSP_008930_1880At the highest resolution given for the index image (you can choose "wallpaper" 2560 x 1600 in the lower right of the web page), each stairstep seems to be separated from the one above it by a layer of dark boulders. Other possibilities might include repeated deposition of thin lava layers or repeated development of awfully strong layers of dark cement on top of each bright layer before the next one was deposited. If dark boulder layers, that would seem to rule out wind as the depositing agent, at least of the boulders. Note: A similar observation of apparent interlayer boulder beds was made by Emily in some other HiRISE images over a year ago, and that observation inspired me to start writing here.
As has been said before, too bad the best exposures on Mars are too steep for rovers.
-- HDP Don