Extended from: http://drupal.org/node/1167744
Realized this support should be moved into a sub-module, despite how dated this post is. Will fix when I have time.
Perhaps this should be merged with #1305662: Add Views support?
Here's an updated patch. I didn't see any cross dependencies between ctools and views support for this, so at the moment, I'll keep them apart.
Moved into Masquerade Extras.
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