What you do online, at least when you're doing it from work, is your employer's business and not much of it is private. And the number of companies reading your email is important to note for anyone seeking employment. In fact, almost 17% of the companies surveyed had employees whose primary job is to read or analyze email.
So, it's important to be careful. Don't send job search related (or networking) email from work. It's not worth taking a chance on getting caught. Use your personal email account and send your resumes from your home computer. Job hunt carefully - and confidentially. What if you do get caught? Here's some advice on what to do if the boss catches you job searching.