This Google page refers to a "DART Iframe". Does DART stand for something? I seem to be missing some crucial piece of cultural understanding.
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This page provides a link to the answer: http://www.applecider.org/forums/viewtopic.php?id=917
"After a quick google search for "Dartiframe.html", this looks to be a filename associated with the company "doubleclick", who is involved with online advertising."
Also at this site: http://www.webmasterworld.com/google_adsense/3773640.htm
I've done a little research and dartiframe seems to be a file you would install if you were using doubleclick and wanted media ads to break out of their iframe.