I did
Oh yes! Few times in my life. It is really amazing. Last time was two months ago with a fuck buddy I have. And there is a masseur named Carlos on Union Square NYC I experienced it 3 times with...It feels amazing, the only thing is that I always love cumming together with my top, and most of the times cumming hand free is a sudden unexpected event that the top can't "pair" with.
Not sure what anal orgasm feels like, I don't think I ever experienced it, but if it would be an addendum to cumming hand free while being fucked it must be super amazing!