ClickToFlash will block all Adobe Flash in Safari for you until you call upon it to show the content. The bonus is that when visiting sites like YouTube, you have the option to view the video in H.264 / Quicktime and even download the video to save to your computer. *I plan on doing this to build up my music video library.
For Mac users (especially Macbooks) this is going to keep your machine cooler and save you gobs of battery life visiting all those nefarious blogs using flash to publish advertising.
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