Sure, you have satellite radio and you're addicted to it, but do you really know how it works? Maybe not, but for those folks aspiring to hit it big on "Jeopordy" when they have a "Satellite Radio" category will appreciate this.

Did you know that XM has two satellites in a Geostationary Earth Orbit (GEO), while SIRIUS has three satellites in an inclined elliptical constellation? This means that XM's satellites are always in the same place relative to you, while the SIRIUS satellites are constantly on the move. How about this little tidbit: SIRIUS was originally called "CD Radio", while XM's original name was "American Mobile Radio"

I suppose at the end of the day, most satellite radio subscribers just want to turn on their radio and hear music. For the Trivial Pursuit players in the audience, look for more interesting facts at the How Stuff Works page on Satellite Radio.