A couple weeks ago I was out running a few errands en femme when I decided to go through the drive-up at my favorite coffee shop. I had a few other things on my mind and I wasn't really paying attention to my voice. I mumbled a bit, and the girl taking the order (who couldn't see me) said "will you repeat that sir?"
I also got a couple of amused smiles at the window, when I got there. I expected that, because I don't pass all that well, but the "sir" really annoyed me.
So, a couple of days later I was passing the same coffee shop, this time in drab -- with the suit and tie and everything. Once again I decided to go through the drive-up. As I was waiting to order I decided I was going to "get even" with them for calling me sir. So this time I ordered in my very best female voice. When I got up to the window, my drink was ready and waiting. But instead of giving it to me, the girl at the window gets this really confused look on her face, and starts digging through her orders. She even left the window to go talk to her boss. Finally she came back and said "did you have the ... ?" I just smiled and said "yes I did," in my normal male voice.
I drove away thinking "ha, ha, ha on you!"