How to find out if someone is gay?

About half a year ago I have listened to a podcast on my MP3-Player - no, I don't have an iPod! - where two girls from Albuquerque where talking about how you could find out if a girl is a lesbian. One suggestion was ...

"Ask the girl if she knows Bette and Tina"

Yes, that made sence. But right now - six month after - it has changed, I think. Now it should be ...

"Ask her if she knows Elka and KC" ... or, as we have learned lately ...

"Ask the girl if she knows Elka and the other one"

Like sloganx always said ... Praise Kelka!

PS: If you don't already do, it's highly recommended to listen to the podcasts mentioned on the right. And there are many more out there.