If you want a low-tech option (no fancy programs involved), see http://www.mvps.org/winhelp2002/hosts.htm, and copy their hosts.txt file to c:\windows\system32\drivers\etc\hosts (no .txt). This tells your web browser to ask your own machine for those ad websites. Oh, but you don't have a webserver on your machine, so it can't load the ads! (Similar approaches work for OSX and Linux, etc.)
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Summer beast; http://i497.photobucket.com/albums/rr34 ... uff015.jpg
Viner Maxima, Tifosi CK7, Giant Bowery, Old commuter.
Blog (incl. bikes)