I was curious about the Google Web Toolkit and
the Google App Engine for longtime, but never get the opportunity to make a try.
Surfing the web, looking for Python's things, I found Pyjamas, a Python-based Web Application Development Framework.
Thanks to the Spam button, any Gmail user can quickly report new SPAM to Google.
Google can collect reports from thousand of users and maintains a list of spamming sources and deny new emails from them.
This list is nothing more than a RBL.
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