Firesheep is a recently released add-on for Firefox that lets you hijack people's browsing sessions on open wifi networks. It works by sniffing cookies, lets you see who is logged into what around you (eg Facebook, Twitter, Amazon etc etc) and simply click to hijack their session. This is certainly coming to an internet cafe near you, so logging into sites that do not use https:// on open wifi networks is probably a very bad idea.

Sites that use encrypted connections (https://) are ok, so long as they stay encrypted. Wireless networks that use WPA encryption are also ok.

More information about Firesheep.

I wonder if the Android Gmail app uses https for the connection. Anyone know?