Caught an interesting article this weekend out of the AOPA_epilot newsletter. It looks like the famous Groom Lake research facility, also known as Area 51 has got an ICAO identifier now, KXTA listed as Homey airport. While it hasn't quite made it onto AirNav just yet, you can look it up on some Jeppesen products and maybe even in your GPS. Just don't plan on using it as a waypoint anytime soon, that is unless you want a little formation time with the local fighter escort.