Interplanetary space junkies will have a treat in the next upcoming days: Mercury will be imaged by the MESSENGER spacecraft. In fact, it already has, according to the site: here's the first photo of Mercury by MESSENGER:
The first of eight navigational photos have been received. The spacecraft features two cameras: a wide-angle camera, or WAC, and a narrow-angle camera, or the NAC. To assist in navigation, the WAC takes photos of the starry background, and the NAC, which photographs the planet. Since the stars are so far away, they may as well be 'fixed' in space, and, in conjunction with the planet photograph, are used to determine exact position and if any adjustments need to be made. Stay tuned for more Mercury photographs as they become available!