The Wolfram|Alpha blog lists a couple of great tricks, including:

• the ability to identify the stars in the sky based on your location
• looking up information about a specific star’s distance, brightness, spectral class (astronomy nerds out there know the “Oh Be A Fine Girl Kiss Me!” classification system), mass, and even surface temperature!
• looking up information about the next lunar and solar eclipses, sunrises, and sunsets
• looking up general information about the planets in the solar system

What I find most impressive, however, is Wolfram|Alpha’s ability to generate graphical depictions of the information you’re looking for, whether it be understanding what you’ll see when you look up in the sky:

Visualizing the path of the sun for a particular day:

Or getting a sense of the 3-body-configuration of the sun, moon, and earth:

Chalk this up as yet another cool thing you can do with Wolfram|Alpha!

(Image credit: Wolfram|Alpha and Wolfram|Alpha blog)