Don't get me wrong. I think web site owners deserve to be paid for the value that they afford me. If I find a site particularly useful, I'll click an ad or two to say thanks. But there are some ads that I despise. Particularly ads that move. So I usually have the AdBlock extension installed in FireFox. I happened to miss it when building up my new Mac Mini, but installed it recently, and soon after started noticing an odd bug. Occasionally, flash objects would flicker, then disappear when I scrolled a page. They would reappear as soon as the top edge crossed out of the view port. As long as the entire object was within the view port, it would disappear. It made no difference if the object was an ad or not. I decided to hunt down the bug and found that it was AdBlock's "Show Tabs on Flash and Java" option that was the culprit. Disabling this option removes the cluttering translucent tabs, and preserves the page content.