Today's Image of Mars is the first ever full color HiRISE image taken of the Spirit lander. While the lander has been imaged by HiRISE before, each of those images was in black and white and didn't really show how much the lander stood out against the Martian surface.
You can see the Spirit lander on the west side of Bonnerville Crater bottom left of the image. You'll notice it is still brighter than the surrounding terrain, but it has acquired a 'Martian hue' because of the dust cover.
Clicking on this image will take you to the high resolution image from HiRISE, where you can better see the Spirit lander. [See the caption from HiRISE]