I think the most amusing experience I had was in IJK (Izhevsk, Russia). Security was a WTMD, but the lady manning the detector saw my insulin pump and motioned to take it off. My Russian doesn't extend to explaining insulin pumps but I showed her it was attached to me and couldn't come off. She then seemed to decide it was some kind of pacemaker, wouldn't let me through the WTMD, sent me round it and gave me the briefest wanding I have ever had.
I didn't even opt out