Do you wear varifocal glasses? A few years ago I developed severe neck problems and found that I was unconsciously tilting my head slightly to view a monitor. After a new prescription for VDU/Reading Glasses and treatment on my neck the problem has now gone, hopefully for good.

"...if necessary I pop a couple of Paracetomal in the early hours."

That's fine, provided it only happens on rare occasions. If it becomes a regular occurrence something is wrong.

I spend a good deal of time working with three screens arranged in a semicircle. In the old days of CRT monitors I suffered from eye strain and the occasional headache, but since the advent of modern flat screens I've been fine - not a single headache or case of eye-strain.

A very important factor is a good chair - bad posture will definitely result in shoulder and neck pains.

Doesn't Boris have a mouse-mat...while he catnaps ;o]