The large amounts of money the Government seem to have got their hands on, has been built up over many years from the Consolidated fund. Some of this money finds itself in the Contingencies fund (2% of the annual budget) which puts aside money for unexpected disasters which may hit the country (Foot and Mouth disease for example).
http://en.wikipedia.org/wiki/Consolidated_fund
In this instance, yes, our money is going to prop up these failed businesses (banks). And yes, they will then use that money to make money from us individuals.
It is not the Governments job to run commercial banks and the the current banks that have been nationalised will need to be privatised again asap.
Remember what happened last time Government assets were privatised. The incumbent government bought the election with "the share owning democracy' (we bought shares cheap off the government and sold them a few days later for their real price). It was supposed the bring competition into the Gas, Electricity and Water markets. Instead, the taxpayers just were ripped off.
Brown is said to be an admirer of Margaret Thatcher, is he about to pull off the same trick trick?