If you ask snopes maybe you can use there database of claims. You could start by throwing out all claims that snopes doesn't classify as true or false.

Example claim from http://www.snopes.com/business/money/money.asp: According to snopes the rumour that U.S. law specifies that a creditor does not have to accept more than 100 pennies towards the payment of a debt or obligation.

A) True - B) False

When the user answered the software presents him with "False" and gives him a link to the snopes website where the user can read more information.

Snopes would profit from having more people exposed to their database and those people being directed with link to the snopes website.

I don't know whether the Snopes folks would be open to having their database used in that way, but asking won't hurt.