Here are few prebuilt connector which from TableauJunkie and Interworks allow users copy URL below ans paste into Web Data Connector to play with :

Facebook

http://ec2-52-10-150-250.us-west-.compute.amazonaws.com/facebooksearch/pagefeedwebconnect.html

Twitter (only be available for limited time)

http://ec2-52-10-150-250.us-west-2.compute.amazonaws.com/twittersearch/twitterwebconnect.html

Weather Analysis

http://ec2-52-10-150-250.us-west-2.compute.amazonaws.com/weathersearch/weatherwebconnect.html

USGS Earthquake

http://ec2-52-10-150-250.us-west-2.compute.amazonaws.com/earthquakesearch/earthquakewebconnect.html

Import.io

connectors.poc.interworks.com/importio-magic  (which tries to automatically find a list and structure it for you)

connectors.poc.interworks.com/importio-api (which allow you to access data by enter Import.io api query)

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