Activist and blogger Ramy Raoof posted this photo of a protest sign earlier in the day Friday.

Blogger Zeinobia, having just returned to Cairo, posted this video of people celebrating in the streets with honking horns and shots fired into the air.

Also, cyber activists are urging each other via tweets to help clean up Cairo's Tahrir Square, starting Saturday.

"We need to clean the garbage and leave the memorial parts... not to leave unclean things after us." tweeted Mo Elnadi.

"It is our duty," tweeted Google staffer and protest leader Wael Ghonim.

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--  Molly Hennessy-Fiske