Someone I worked with was fired for looking at the internet. He was looking at porn sites an avergae of 4 hours a day!! He tried to say it was work related, but manager asked what searching for "soft suck" had to do with his job........
I don't know anyone who has been sacked for this at all - so far ... However I did have a chat with a senior manager about it and he said it was a case of if a company was looking to get rid of someone, then looking at the internet for 'non-business' purposes could potentially be used. Apparently the fact that everyone else does it would not be any defence either The last 3 companies I worked for had this warning in their contracts. However you could also get done if you were caught pinching office stationary too - so I would guess using the internet for non-biz purposes would be down to your individual managers discretion. Personally I would have thought they would only come down heavily on people who either looked at dodgy sites or those people who were using the net so much at work it was making having a serious effect on their performance.
Not for just using the net for 'normal' stuff, no. But I recently heard that a teacher at the school I used to teach at has been suspended for inappropriate material on his laptop at school.
Dh had to sign a form when he first started work at his new firm to say that Internet use would be only for business use. That seems to have gone by the way side now though. I know DH uses the net to keep up to date with the cricket scores, and he even shown one of the senior partners how to download it too!
I worked for a large accountancy firm in London up until a year ago. I did hear that people had been fired for downloading porn. We also had quite a number of temporary staff and had been informed by our managers to make sure they were not surfing as they were not been employed to do that.. I always used to press the alt tab key when somebody used to creep round the corned when I was surfing and should have been working. I think if you get caught looking a things like Mumsnet, BBc etc you can just say you were using it for research