A very interesting bit of news dropped recently that is going to have profound effects reaching well beyond gaming: Blizzard just created a "Mobile Authenticator"
application for the iPhone.
Essentially, months back the company released a physical device that generates what looks like random numbers, but is actually synced with its servers. When logging in, users enters their password and this number, which theoretically protects against unauthorized remote login, and at very least limits account compromise (trojans are still a problem, though). The problem with this method is, it required a $5 dongle to be sent to users, and then carried around for logins.
The system has been implemented by a number of banks, not just Blizzard. But they have all faced the issue of having to distribute physical devices. Until now. By releasing a mobile app that serves the same purpose, Blizzard has consolidated the functionality of the dedicated device into a mobile phone. The company is planning on rolling the application out to more than just the iPhone, and offering the service for free.
I think it's only a matter of time until we see a major trend toward this two-factor authentication now that it's being incorporated into phones. For financial service companies, these apps will be a great branding opportunity to get on users' phones, and can always have additional services and functionality rolled into them.
Kudos, Blizzard -- this was a very smart move.