Mrs Windsor and Son, have more power than we thought.

The extent of the Queen and Prince Charles's secretive power of veto over new laws has been exposed after Downing Street lost its battle to keep information about its application secret.

The Guardian reports that  

Whitehall papers prepared by Cabinet Office lawyers show that overall at least 39 bills have been subject to the most senior royals' little-known power to consent to or block new laws. They also reveal the power has been used to torpedo proposed legislation relating to decisions about the country going to war.
The internal Whitehall pamphlet was only released following a court order and shows ministers and civil servants are obliged to consult the Queen and Prince Charles in greater detail and over more areas of legislation than was previously understood.
The new laws that were required to receive the seal of approval from the Queen or Prince Charles cover issues from higher education and paternity pay to identity cards and child maintenance.
In one instance the Queen completely vetoed the Military Actions Against Iraq Bill in 1999, a private member's bill that sought to transfer the power to authorise military strikes against Iraq from the monarch to parliament.
She was even asked to consent to the Civil Partnership Act 2004 because it contained a declaration about the validity of a civil partnership that would bind her.
In the pamphlet, the Parliamentary Counsel warns civil servants that if consent is not forthcoming there is a risk "a major plank of the bill must be removed".

 Guardian 15 January 2013 

Some Examples include

The Queen

Housing Act 1996

Rating (Valuation Act) 1999

Military actions against Iraq (parliamentary approval bill) 1999 – consent not signified

Pollution prevention and control bill (1999)

European Union bill 2004

Civil Partnership Act 2004

Identity cards bill 2004-06

Courts, Tribunals and Enforcement Act 2007

Corporate Manslaughter and Corporate Homicide Act 2007

Fixed term parliaments bill (2010-12 session)

Her Son

Conveyancing and Feudal Reform (Scotland) Act 1970

Land Registration (Scotland Act) 1979

House of Lords Act 1999

Gambling bill 2004-05

Road Safety bill 2004-05

Housing and regeneration bill 2007-08

Energy bill 2007-08

Planning bill 2007-08

Local Democracy, Economic Development and Construction (Lords) 2008-09

Marine and Coastal Access (Lords) 2008-09

You can see some argument that the Head of State, should be consulted on Bills that he or she were expected to sign if they were elected , but unelected ? and her Son and Heir as well.

The guidance states that the Queen's consent is likely to be needed for laws affecting hereditary revenues, personal property or personal interests of the Crown, the Duchy of Lancaster or the Duchy of Cornwall.
Consent is also needed if it affects the Duchy of Cornwall. These guidelines effectively mean the Queen and Charles both have power over laws affecting their sources of private income.
The Queen uses revenues from the Duchy of Lancaster's 19,000 hectares of land and 10 castles to pay for the upkeep of her private homes at Sandringham and Balmoral, while the prince earns £18m-a-year from the Duchy of Cornwall. 

Guardian 15 January 2013 

So the Monarch and her son have a say in their own revenu , Its like the President of the USA ,setting his own wage and retirement package.

The real scandal is there's nothing we can do about it. A MP bringing this up in the commons will be banned by the Speaker  from doing do. Because our elected Democratic institutions do not discus the monarchy in the chamber.

Unless its a sycophantic speech of course.

We need to know the full extent of changes to Government Bills made at the bequest of the Monarch or her heir and if any Bills were dropped because of a "Royal Veto",

In 2010 the people of Wales voted for the Assembly to have some legislative powers should the referendum Question have had the proviso " subject to the Monarchs or her heir's approval?"

Are we to See the same proviso in Party Manifestos?

The Queen should be told her role is to wave at crowds , entertain foreign dignitaries and open buildings.

It should be made clear that she may well express an opinion but it will have no effect on policy.

As arguments are made about devolving power from Westminster and regaining powers from the EU. Perhaps we should start debating ending the powers the Monarch still keeps

But then do we really know what powers she actual maintains?