Stellarium
If you are interested in astronomy and just like to watch the stars at night and wondered what is the name of the star, you have to check out this software – Stellarium (now in v0.10 beta) and it is open source as well and once installed, it does not need internet connection for viewing.
My 4 year old son loved it from the very start and busy clicking on the various stars, planets and nebulas. It is a mini planetarium on a small version
