I regularly clean out my cookies with "delete all", but I'd prefer to keep the ones for sites that require a login. But it's too hard to delete cookies individually.
You can achieve that in Firefox without any extra extensions: Under Privacy: 1. Use Custom settings for history - Accept cookies from sites - Keep until: I close Firefox 2. Under Exceptions: - Add sites you want to allow permanent cookies sites using "Allow" button Done. Sites you allow can store cookies until they expire while other cookies are cleared every time you close the browser.