Has there been any news or stories of Bitcoin being used as collateral for a real estate purchase?  I know it has been used to make the actual purchase but what about as collateral?

Given the nature of the block chain (ie. public ledger), it would be easy for a real estate entity to confirm a signee's Bitcoin ownership has not changed while still staying in possession/control of the signee.

I think the new US regulation will open up a new world of 'Bitcoin as collateral' and less so as a 'currency' per se.