What other sites do flash and other web 2.0 components trust, by Google search or Google hacking the crossdomain xml file, you can find out some very interesting things about what sites are trusted by another site, and where API’s or other trusted widgets can come from, including advertising.

The Google hack is here, crossdomain.xml site:.com or feed in extension .com, .net, .org etc of choice.

This is the crossdomain.xml file from twitter as an example

allow-access-from domain=”*.twitter.com”
allow-access-from domain=”*.discoveringradiance.com”
allow-access-from domain=”*.umusic.com”
allow-access-from domain=”*.hippo.com.au”
allow-access-from domain=”*.ediecareplan.com”
allow-access-from domain=”*.yourminis.com”
allow-access-from domain=”*.korelab.com”

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