Widget-ized API?

Is there examples somewhere on how to simply put an API call into a Piwik Widget?

For example, I want to put this query into a Widget:

Get last 30 days in a graphic:


Some kind of Meta Widget where the workflow would be:
1. Create new Widgewt API
2. Add an API string
3. " Voilà! "

So far this http://amirshk.com/blog/2011/07/08/piwik-custom-data-tracking/ and http://geekmonkey.org/articles/34-how-to-write-a-piwik-plugin are way too much for a human being like me. :wink: