, satellites.
You will be surprised at how many there are cris-crossing the sky. Just last night I had on cross my field of view while I was looking at Eta Carina.
Some have a static shine, others flash as they spin, others change in brilliance as their orientation changes while orbiting Earth. You will even see some totally disappear as the move into Earth's shadow.
Nasa also provides a link to the time, location, direction and brilliance of the International Space Station to where ever on Earth you are located:
http://spaceflight1.nasa.gov/realdata/sightings/
Really cool stuff.
There are even nutters out there that get a kick out of chasing the ISS to photograph it with Earth based scope! Some get really good results too.