Secure Profile is a Google Chrome addon that allows you set up a password to protect your entire Goggle Chrome profile, this is much better than other Chrome privacy addons like Link Password, which only encrypts your bookmarks. After entering a password inside Secure Profile options, before anybody can use your browser they will have to enter the password too, this extension can be used to stop people from using your Internet browser. Different profiles can be set up, all of them with a different password.
You could use one profile/personality to visit certain sites, like news, and switch to a different profile for sites like porn, the advantage would be that tracking cookies on that specific profile will be isolated from others.
Google Chrome Secure Profile addon
This addon also protects your browser in Incognito mode when Google Chrome runs in RAM. It could be of use when sharing a computer at home to make sure everyone has their own settings and cookies, this is an easy solution to stop a noisy person from looking at your browser settings and history.