Once upon a time a guy named J-roen saw a Sesame Street parody site called "Bert is Evil." He liked the site and created the image (below) in homage. Eventually, the image got around on the web. How this picture ended up on protest posters halfway across the world is the interesting part. Read the news stories to get a sense of what happened.

The Bert-Bin Laden Connection? (Oct 10, 2001 - E!Online)
Is Bert truly evil? Has he really forsaken good buddy Ernie for Osama bin Laden?
While the folks behind Sesame Street emphatically say no way, Ernie's longtime partner did indeed pop up on posters with Osama bin Laden.
'Muppet' producers miffed over Bert-bin Laden image (Oct 11, 2001 - CNN)
The producers of the popular children's program "Sesame Street" said Thursday they are upset because protesters in Bangladesh are carrying protest posters showing the Muppet character Bert with Osama bin Laden.
Osama Has a New Friend (Oct 10, 2001 - Wired)
Evil Bert, meet Evil Osama.
Right now, the two appear to be inseparable -- at least on ubiquitous posters carried by pro-Taliban demonstrators.
Bin Laden's Felt-Skinned Henchman? (Oct 14, 2001 - Fox News)
Do the global terror links reach even as far as Sesame Street? Is Bert the Muppet a henchman of terrorist mastermind Usama bin Laden?
Due to the intense media pressure a number of Bert is Evil sites have been discontinued. J-roen took his site offline (archive).
Dino Ignacio of Fractal Cow was the first BiE site on the web. He had second thoughts, too (archive).
For the intensely curious, I suggest a Google search for the various unauthorized mirrors.
One wonders if there is one less Kinko's employee alive in Pakistan.
To the memory of Jim Henson: they hardly knew ye.
here is something I hope is doing no evil.
there could be more of them