LunarSight - Accurate data about the Moon
MOON for Android - Beautifully track the phase of the moon
Lunescope Moon Viewer - Interactive 3D simulation of the moon.
Next Full Moon - All in one calendar to find the next full moon date
Stellarium - Stellarium is a free open source planetarium for your computer.
Solar Walk - Solar Walk is a 3D model of our solar system, bringing the universe to the palm of your hand.