I am intrigued by this weird advisory on cryptome, keeper of, if not all, then at least exclusively, things you are not supposed to know. There's no attribution, no explanation, and no other mention of this on the web.
The very short gist is:
Avoid the treacherous anonymous web browser, bangotango.com. It is harvesting unwary user addresses. It is operated by triumphpc.com as a law enforcement/intelligence sting.
It would be an interesting concept, if only because it has such problems with the idea of entrapment. The idea that the some agency could make the promise of proxied worry free browsing, even going so far as to include the text of the 4th amendment on the website, and then use evidence gathered there in court is boggling.