Michael Perelman has suggested that banks may serve a public utility function and should be nationalized. I assume he means the functions of holding people's money as deposits and using it for some sort of basic investing, without getting into fees for packaging mortgages or other more exotic financial activities. I suggested in a comment on his post that a model of this might be the old postal savings banks of much of Europe and Japan, the latter being the largest in the world. I do think something along their lines, however owned, might offer an alternative, simple banks that do simple things.
As it is the current trend is for those old banks to be privatized in some form. This happened finally in Japan in October, 2007, to the Japan Post, which does more than serve as a bank. In today's NY Times is a story that there is a move by Post A.G., Deutsche Bank, and Swiss Reinsurance to take over the still nationally owned Post Bank A.G of Germany, their postal savings bank. See http://query.nytimes.com/gst/fullpage.html?res=9E02E7D91439F930A35753C1A063958260.