Love the Noscript. But it's not for the faint of heart. In fact I think you need to be a little .. um.. anal.

Other good Firefox plugins:

BetterPrivacy (addons.mozilla.org)will delete the flash cookies on exit

Https-everywhere (www.eff.org) will auto-enable https on mainstream sites like Google and Youtube. Brought to you by EFF.

There's a slew of plugins really for Firefox and people have made collections on Firefox's plugin/extension site if you need more of them.