Slightly off topic, it was fascinating to see on the tellybox, an interview with a 65 year old lady who has an inability to feel pain. Apparently this was first noticed at the age of 7 when she broke her arm and it was her mother who noticed that her arm was hanging at a weird angle. The phenomenon is being investigated and so far the medics have found the presence of a high concentration of some natural chemical. Might be of some use in the future.
I'm not sure whether the inability to feel pain is a good or bad thing - it's certainly a good way of telling you that something's wrong. Was important once for me when I woke up feeling a slight pain all over my body. Very strange and usually I ignore. Nothing else appeared wrong, but in hospital I was told that had I waited a few more hours, I would have been on my way through the PGs. Gulp.
I'm sure that people who suffer chronic pain though would love to be in the lady's position.