In a backyard with nothing blocking the view and in the ladies washroom at the Walmart.
I did stroke off at work a few times early on in my Lush days. I was chatting on ! Messenger with a woman who I met on another site but who also posted here back then (she's gone now, I'm pretty sure). Retreated to the men's room when I got close to blowing, though, so never actually came at my desk.
And on my previous job, I used to have the building to myself when I backed up the main system on Saturday nights (took like ten of the old school open reel tapes so had to stay there to change tapes). So I did get off during those nights sometimes.
Learning to draw the human body becomes a lesson of another kind.
The woman by the pool shared her art ... and so much more.
Lucy's Body of Art - Wherefore Art Thou comp entry