Wasn't expecting that!

...bah fill it up in a min as normally the light comes on with loads of warning. The bastard thing was at the redline when I looked! 120degrees plus!!! so I was about 2-3 mins from work and went in at tickover in 5th as stopping was not an option on the roads I was on. Oil in the coolant resovoir confirmed it is the head, I am now lookingg at a repair bill of 500-700 if no other damage occured.     I...