I had a very strange dream last night. I can't remember all of it, but I had been "sentenced" to be hung upside down for an hour by my ankles. I had to wait my turn, as someone else was hanging before me, and I was terrified. I knew it would hurt and I was afraid the blood would rush to my head and make me pass out or worse. This was not an offical sentencing, like in a court, but I had to do it.
When my turn came, there was an elaborate mechanism there, with padded bars for my ankles and some kind of chain that hoisted me up. I woke up just as they were using it, and I couldn't get back to sleep.
There seemed to be a hint of this being erotic, although no one else was involved and I did not become aroused. Prehaps that was due to the submission involved.