This is one of the coolest GPS applications I've ever seen: the Celestron SkySkout. Look at the night sky through this handheld unit, and the SkyScout tells you what you are looking at. There's a screen on the side that will give you the name of the star, the planet, or the other astronomical feature, as well as any information on it (for the most popular objects, such as the planets and the close stars). It will also speak to you and read off the name.
The SkyScout will also provide "tours" of the night sky--it'll tell you which way to turn to see particular objects. You can use a PC to download new tours and data to an SD card, which is where the SkyScout's data is stored.
In addition to a GPS sensor, to locate you on Earth, the product has gravitation sensors so it knows what angle it's being held at. Spokespeople also told me the grav sensors tell the unit which direction it's pointing, although I suspect a simple electronic compass does that task.
If you've ever stood outside on a clear night with a child who looked to the sky then to you, asking for an explanation of a constellation or other bright spot of light, you might have wished for this gizmo to help maintain your kid cred. It'll ship in March for $399.