In honor of Star Trek's 40th anniversary, though you need not be a Trekkie to enjoy this... This free space simulation program lets you look at the entire universe in three dimensions. Sure, you can look at Earth, but you can also travel from the comfort of your computer chair to any of over 100,000 stars, or even beyond the galaxy. You can even visit Federation star ships if you wish. As the developers state, the exponential zoom feature lets you explore space across a huge range of scales, from galaxy clusters down to spacecraft only a few meters across. A 'point-and-goto' interface makes it simple to navigate through the universe to the object you want to visit. Have fun.