I registered specifically for this thread. I guarantee you that I have felt an x-ray before. I have felt it MULTIPLE times. It feels like a tingling or a very low current going through the portion of your body being x-rayed or whatever. The first time i told the doctor and he was like thats interesting. The second time (months later) i had forgotten completely about it. Im standing there getting my knee x-ray (i play sports) and i feel it again. and if feel it for every x-ray after that, they usually do like 3 each session so i guess i've felt it maybe 6 times.
weird though... i have gotten x-rays in the past and didnt start feeling them up until about a year ago (i am 21 now)
Honestly, I am 99% sure that this was no placebo. I would be willing to prove it to.