The essence of banking is intermediating between buyers and sellers of the time value of money -- except they're called borrowers and savers.
Just as E-Bay brought this intermediary role into a new place with hard goods of all types, a service called Zopa hope to do this with borrowing and lending money.
The driving force behind this innovation appears to be the distaste some kinds of borrowers -- and investors -- have with the whole banking experience. Zopa's creators had economists helping them, sure, but they also had ethnographers.
Stay tuned, this could get pretty interesting.