http://www.theatlantic.com/business/arc ... is/250121/
http://research.stlouisfed.org/conferen ... _Order.pdf
http://economistsview.typepad.com/econo ... e-cra.html
Negligible.
Again, guys, if the housing bubble caused all of this we would've only had a housing bust. We did not. Corporations, huge corporations, were funding themselves day to day. Derivatives were used. CDO' and CDS' were used. AIG didn't go under because of a housing bubble - they went under because of the bets made against them, the money they owed on the impossible guarantees they made, and banks closing all doors at once.
In a nutshell - the market itself became illiquid. Cash didn't matter. Money wasn't changing hands. Subprime mortgages, no matter where they originated from, did not cause that.