Worstall on Wednesday Here's a great get-rich-quick idea: Go build a bank. No, really, it's an industry that's ripe for the plucking at present.

One way to think about banking is to divide it into four different types: transaction, savings, commercial and investment. Investment banking is all that City-style markets 'n' stuff; commercial is trying to work out to whom you should lend money; savings is flogging savings certificates to retail punters; and the latter, transactional banking, is what we should concern ourselves with here today. People need to be able to put their wage packet into an account and then use some system to be able to pay their bills and get a bit of cash from an ATM.

This sort of banking, transactional banking, is essentially a girt big computer system with a packet of licences attached to the side of it. Those licences make it difficult and expensive to enter the business, but rather like castles, the higher the walls to entry, the greater the plunder if you can actually manage to break in.