Firesheep - A Firefox extension that demonstrates HTTP session hijacking attacks.
Firesheep , a Firefox extension designed to demonstrate just how serious this problem is. After installing the extension you'll see a new sidebar. Connect to any busy open wifi network and click the big "Start Capturing" button. Then wait. System Requirements Mac OS X: 10.5 or newer on an Intel processor. Windows: XP or newer. Install Winpcap first! Linux: Not currently supported. Firefox: 3.6.12 or newer. 32-bit only. Firefox 4.x beta not supported. Download Download (OS X, Windows) Source Getting Help Discussion Group Bug Reports More Information Blog Slides from Toorcon 12 Talk