Today has seen the publication of the annual report of the Royal Public Finances, a summary of which is downloadable here (as a pdf file).
The main conclusion from the figures is that the Queen effectively costs us each just 69p a year, which is pretty good value, I would venture.
But interestingly, she appears to have felt the need for something of a spin operation to promote this fact to Members of Parliament.
Here's the letter the "Keeper of the Privy Purse" has sent this afternoon to all MPs...