I was searching for some info on a tool I occasionally use, and one of the Google links took me to about.com. I was really surprised by the amount of junk on the page -- normally I don't pay a lot of attention to about.com since I've got the loud ads handled, but as I scrolled down the page there was this tiny bar that appeared and scrolled down the page with me. Unacceptable.
Luckily, everything ugly on the page (besides their layout) resides in
numbered directories on z.about.com, using this format:
the solution is to block everything in numbered directories on z.about.com.
Here's my new
filter that handles this case:
It begins and ends with a slash so that Adblock knows to interpret the entire
thing as an expression. Without them the filter would be a primitive
"http://z.about.com/*", which might block more than I want. Expressions allow
me to be more specific. The
^ indicates that I want the URL to begin with
the following text. I have
 around slashes and periods because otherwise
they would be interpretted as things other than slashes and periods. The
indicates that any digit from 0-9 will fit.
Taken all together, if Adblock sees a URL that starts with
http://z.about.com/ and the first directory is a single number, it will
block whatever was going to be loaded.