How do YOU avoid getting distracted by the Internet?

Some writers are able to switch off their computers and stay off e-mail and the Web all day. Freelance writers who rely at least partly on client work for income, however, sometimes don't have this luxury. The Internet can be a wonderful resource for writers but it can also be a major timesuck.

To those who DO have to go online at least a few times a day: How do you manage your time online? Do you limit the amount of time you spend on social networking sites? What tricks and tips can you...