Astronomy - Stellarium
Stellarium is a free (open source) planetarium for your computer.
It shows a realistic sky in 3D, just like what you see with the naked eye, binoculars or a telescope. It is being used in planetarium projectors.
Stellarium has real time and real wheather allowing you to see exactly whats ouside!
You can download it for Mac or Windows. Click on the link at the top to enter the site then on the left menu colmn select either 'for Mac' or 'for Windows'
I have dowloaded it and think that it is great.
Once you have dowloaded it and opened it you will see a menu bar at the bottom left of the screen. There you will find lots of buttons, try them to see what they do! One of the buttons is the settings where you can enter your cordinates of where ever you may be.
Here is a video I found on You Tube with someone explaining Stellarium: Stellarium Video