Cafe Crack, provides a platform built from open source software for deploying rogue access points and sophisticated Man-in-the-Middle attacks.They make it look easy:
Using only a laptop, the attacker can sit unassumingly in a public location to steal personal information. Perhaps the most alarming aspect of this demonstration is that it was accomplished with only a laptop and existing open-source software.I knew it could be done, but I thought it was harder than that.
There are things that corporations can do, like spin up VPN’s:
However, the good news is that it is just as easy to protect oneself against Man-in-the-Middle attacks on an unsecure wireless connection. By using DNSSEC or VPN services, the user can bypass the attacker and keep their information secure.But for ordinary users?
In the end, it is up to the user to be knowledgeable and safe around unsecure technology like public wireless.I think ordinary users don’t have a chance.
Update (07/06/2012): The FBI warned on this type of attack..
 Cafe Cracks: Attacks on Unsecured Wireless Networks, Paul Moceri and Troy Ruths