element hiding helper
https://addons.mozilla.org/en-US/firefox/addon/4364
platypus
https://addons.mozilla.org/en-US/firefox/addon/737
or the context menu power of IE addon adblockpro.com -- that allows one to right-click on a flash object to select it for blocking (no tabs required like adblock plus)
yarip
https://addons.mozilla.org/en-US/firefox/addon/7211
or
rip
https://addons.mozilla.org/en-US/firefox/addon/521
