Windows and Linux with Firefox: Free Firefox extension CookiePie manages Firefox’s cookies—small bits of text stored on your computer that tell a site you’re logged in, for example—in such a way that you can log into the same site multiple times. Just right-click a new tab when you want to double-login and toggle CookiePie for that tab. A cookie icon will appear next to the close button and you’re ready to multi-login. Once CookiePie is enabled, you can easily log into multiple Gmail, Flickr, or Facebook accounts. We’ve shown you other methods to achieve multiple logins once before, but CookiePie is a much more simple, elegant solution. CookiePie is free, Firefox only, currently works only on Windows and Linux.