The Mars Rover Spirit at the foot of the Columbia Hills in Gusev Crater has transmitted images from its microscopic camera that bear a resemblance to fossilised corals.
Here is the link to the page, http://marsrovers.jpl.nasa.gov/gallery/all/spirit.html
You will find references to this remarkable rock formation in the cautious press briefing last Friday linked to the main page at marsrovers.jpl.nasa.gov
At each camera file you must first select the 'sol' or Martian day, then click on the 'selected sol' at the bottom of the menu.
If you go back in the microscopic camera file you will find about 12 days ago the first astonishing images of this piece of rock. It is taking NASA a long time to hold media conferences on the data anyone can read in near real time. For example, we saw from the panoramic camera file on 'sol' 159 that Spirit had reach the Columbia Hills 48 hours before the official annoucement, as images came in from a low rise on the hillside looking down on the main floor of the crater and showing distant glimpses of the main crater wall.
Whether or not these images disclose past biological activity they are very weird and perhaps of immense significance among the small steps we have taken into the cosmos.
(My thanks to Sinlock for directing me from Civil Aviation to this forum.)