Junk Buster

JunkBuster (http://www.junkbuster.com) is a free Web proxy which can filter out anything that can be described with RegularExpressions.

There is also a variant junkbuster with some additional niceties at http://www.waldherr.org/.

Note that development on JunkBuster has slowed or stopped. (Correct this if wrong.)

Alternatives

One of its successors, Privoxy (http://www.privoxy.org/), is so good that I've never had to add a single entry to its list of sites to block.

CategorySoftwareTool

Another tool to use with Privoxy that anonymizes you Internet activity is http://tor.eff.org/. Use it in conjunction with Privoxy, it is not a solution to complete anonimy, but it is a great leap forward.

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