A little “bug” in Google Calendar allow you to find out the name of any person behind any gmail.com email account (if the person registered with his own real name that is).

How to do it:

• Get a Google Calendar account at http://www.google.com/
• Select “Share this calendar”
• Fill in the email address of the person to look up (works only with @gmail.com addresses and companies using gmail with their own domain name)
• Click on “Add person” and hit save
• Next time you check you will see the name of the person behind the account

Google are aware of this since if you fill in the admin email for gmail you get the name “smart ass“:

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