Lee Kaplan of FrontPage Magazine pretended to be a pro-Paleostinian activist and briefly infiltrated the Intellectual Self-sodomy International Solidarity Movement. His story is told here: Part 1, Part 2. An absolute must-read, but make sure you've got some stomach pills on hand. (Hat tip: Israellycool.)
Update: Lee's gender corrected. Sorry for guessing wrong when I first posted this!
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