Yes, actually, to the best of my knowledge, I have never *successfully* flashed anyone. At age 18 1/2, I stepped out of the bathroom after a shower, still wrapped in a towel. I stood directly in front of my girlfriend (like, almost nose to nose) and removed the towel. She maintained eye contact and told me her parents might come in so I should get dressed. She never looked down (good Catholic girl). That was my only attempted flashing. Sad but true.
I do, however, sometimes go nude in my back yard. I suppose if the neighbors put their faces to the fence to peek through the slats, they might see me. But that's them being voyeurs (or voyeuses) rather than me being a flasher.
Man, I have led SUCH a dull life...