NASA maintains a number of useful and fascinating websites. my favorite is their astronomy picture of the day, http://antwrp.gsfc.nasa.gov/apod/ . the image for today, 6 may 2008, is especially breathtaking -- two galaxies colliding, a swirling mass of chaotic beauty.
please note that to view a particular day's image, you must click on the "calendar" link at the bottom of the webpage, then navigate to the date in question. or, it's fun just to cycle back randomly to previous images, using either the "calendar" or the "archive" link.
many of the images are taken from the hubble space telescope, from orbiting shuttles and stations, as well as from ground telescopes. there are also stunning images of terrestrial weather. if you send the above link to your computer's desktop, you can check each new day's image as part of your routine, for a daily dose of awe and wonder. check it out.