Delete unwanted Firefox cookies but keep the ones you need.
Platform: Windows 8 compatible, Windows Vista 64-bit, Windows 7, Windows 7 64-bit, Windows Vista, Windows XP
License: Free for personal use only
Biscuit is an addon for Firefox that helps you remove unwanted cookies.
Once installed, simply click Tools > Show Cookies and the addon will display a new dialog showing your current cookies. You can then delete individual items the entire set.
You can also keep all the cookies that make like easier, such as login details for certain sites.
One othe incredibly handy option is "cancel cookie preservation temporarily". This enables you to wipe all your cookies on demand, while still preserving them in future.