If I'm at the FBO, I'll just say that I fly for the company who owns that plane out there. If I'm at the hotel bar, I just say that I'm I'm town for the EPA conference. I'm a supervisor for trash pickup in Birmingham, Alabama. When they start to laugh, I say, "Don't laugh! You'd be suprised at what people throw away. I've got all kinds of stuff at my house!"
That line actually got me laid by a G-IV F/A in ABQ!
Then I just sit there listening to all the pther pilots making themselves look like jerks playing "There I Was" one after another.