I think this is pretty standard. My position is that much of this is acceptable as long as there are clear rules within the company. I find sometimes that employees look totally puzzled if told that it is easy for their employer to find out what they are watching online. I know that everybody is thinking porn when I said that but actually I was refering to a friend who is diabetic but hasn't told his workplace and got worried about that or people looking for anohter job at work etc.. I don't see much justification for a company to look into private emails though. I don't think it happen too often it is of course inherently possible in the technology. Clarity always help