Does it just seem that way, or did the appearance of Mozilla’s image blocking feature coincide with a decision by Internet advertisers to make every single gooddamn king-sized annoying ad with Flash?
Perhaps it was just the zeitgeist, or the appearence of Flash 6, but I wouldn’t rule that out. Web advertising loves the cutting edge – it needs it to dodge banner-blocking technology.
Some people just deleted Flash. Phil Ringnalda linked to a CSS2 solution you can use with Mozilla: add style rules to your userStyle.css file that hide embed tags of a certain size common for ads.
The user style sheet trick didn’t work for me on the first couple of sites I tried, though, probably because all their ads aren’t really Flash, but IFRAMEs with external source files (on advertising servers).
Killing off all the IFRAMEs on a page is trivial with a bookmarklet, and cleans up ads wonderfully. The problem is it’s not automatic – you need to click the bookmarklet, which means the ads have to annoy you enough for you to bother clicking the bookmarklet.
You could probably do this in a user stylesheet too – apply the style rules to IFRAME tags rather then EMBED tags.