I am a big fan of the Hubble Space Telescope and I visually anticipate the new James Webb Space Telescope (JWST) now scheduled for a 2014 launch. Politics and budget deficits may have even more impact on that launch window then the already two year delay but us galaxy-gazers have cosmic faith.
The photo above of the Sombrero Galaxy was voted the best picture taken by the Hubble. You can see the top ten Hubble images here and on NASA's hubblesite. Besides providing brilliant images from far beyond our galaxy, not to mention great desktop backgrounds (I am currently using the Tarantula Nebula); the Hubble also has accumulated hard scientific data that will be under analysis for decades.
This is the Cone Nebula, which is about 2.5 light years long and growing or expanding to be more precise. If you are feeling like a new desktop image, might I suggest the 80+ options of Hubble Wallpaper. I recommend that you avoid the Omega Centauri globular cluster, I know someone who lost a manuscript on just such a desktop.