I don't know of anywhere that allows you to create/destroy accounts on the fly, but both Egg and Sainsbury's Bank allow you to open multiple named savings accounts for this purpose. The bad news is that these are savings accounts rather than current accounts, so they don't come with a debit card or the facility to accept direct debits. This might be enough, however, to allow you to use a current account for bills and a number of savings accounts for longer-term pots of money which you're prepared to transfer manually when required. To the best of my knowledge, if you want your "luxuries" account (or similar) to have a debit card on it, you'll need multiple current accounts from separate banks.
Usual disclaimer: I'm not an expert; this is my opinion and you take it or leave it at your own risk.