I was thrilled to find this not only revealing, but beautiful picture of a feature I'd noticed many times, but had never been able to find in high resolution.
The pictures I finally found exceeded my expectations. This is something anyone who has wondered about water on Mars needs to see.

To start, I'd like to show you the image that first alerted me to this particular feature,
The arrow points to an object that stood out. This is in the Centauri Montes region.

M0101952
http://www.msss.com/moc_gallery/ab1_m04/images/M0101952.html

This is a piece of the stunning M0404175, a close-up from the above feature.
http://www.msss.com/moc_gallery/ab1_m04/images/M0404175.html

Click image for high res

As I see it, this is one of the most self explanatory features in the images to date. There appear to be ice flows running from a layer exposed along the edge of the crater: This strongly indicates that there is a subsurface aquifer, and it is leaching out in pretty good amount. As extra evidence of this I cite the sunken areas beyond the rim, pointed out by the arrows on the lower picture. We know from experience that as groundwater is lost, sinkholes appear and the surrounding area subsides. It is very probable to me that the debris field at the bottom of this crater is the result of melt, refreeze, and evaporation carrying material slowly to the center.

Note the trenched flows all along the sides.

 The oddity I've pointed out has been specially retargeted by MGS.
Slightly different angle and resolution, same ice covered leaching feature and associated structures.
This one is rectified N/S, and though showing the same area, is oppositely aligned from the image above.

M2000028
 http://www.msss.com/moc_gallery/m19_m23/images/M20/M2000028.html

Well..... isn't this something... Seems like maybe NASA's catching up! Perhaps somebody there has seen this page, because what's in this image is exactly what they're showing in this graphic.

"This is a model to explain a process that might have led to the
formation of newly discovered features on Mars that suggest there
may be current sources of liquid water at or near the surface.
The model shows how it would be possible for water to flow down
the gullies instead of just boiling off the surface. When water
evaporates it cools the ground, which would cause the water
behind the initial seepage site to freeze. This would result in
pressure building up behind an 'ice dam'. Ultimately, the dam
would break and send a flood down the gully." -Ken Edgett, MSSS
 

http://science.nasa.gov/headlines/y2000/ast29jun_1m.htm

Amazing, because I'd had this page up for nearly three months at the date of that article.

And now, to beat it all, we've got a later image that shows newly formed ice, just under these flows.

http://photojournal.jpl.nasa.gov/catalog/PIA09028

Now they're saying that MRO's CRISM failed to find any hint of water at the above area;

I say Look again, a bit closer and a bit more in context

Flowproof