How do the British royal family finance themselves?

Just to add some clarity to the last answer:
Please bear in mind certain points of contention here.

1) The royals family has recently been granted a new private jet by parliment (27-10-08) If the royal families pockets are so apparently deep as the last answer suggests then why are we having to fund thier new private jet??

2) The cost of the royal family from the civil list does not take into account certain aspects such as: Security (estimated to be in excess of £40,000,000.00 in 2007.) This cannot be confirmed as the information is not available due to the fact it is not properly monitered. But you do the maths: a simple day out round london for the queen includes several vehicles containing body gaurds usually ex special forces on daily hire many earning £1000 per day. Of this there will be at least usually 12 of these men "On close protection" (I.e actually near the queen) A support team of god know how many will be around in the local area as well the days before they will be employed in planning the route through the city as well as Int gathering.) The cars used will be bullet proof, bomb proof etc and cost a fortune. These are replaced annually to ensure integrity.
On hand police: Officers taken off thier usual beat to add crowd control and protection. You've all seen pics of the queen on walk about and the sheer volume of police there. Also bear in mind that armed police cost a lot more to pay than the average policeman.
An ambualnce is put on local standby in case anything does happen to the queen. (This vehicle is no longer available for use by the Public until the visit is over)
Drains and manhole covers are searched and checked for devices as well as pins etc costing a small fortune. This is just the very surface of the cost the list is endless!

All this is just for a walk around London. Can you imagine what an international visit costs!

in 1994 Prince charles crashed the royal plane. Who picked up the bill? The queen with her apparently deep pockets?? err no its was us the taxpayer.

The upkeep of estates such as Windsor Castle is part of the reason tax money is paid to the queen so these sites of heritage can be maintained. Thats sounds reasonable to me. So why do I then have to pay again if I want to go and look inside the castle.

DO NOT BELIEVE WE NEED THEM FOR TOURISM!

Without the royal family the castles and culture will still be there!
Many People say to this "People only come to these sights to see the queen!" Well how many tourists actually so see the queen? Very few I can say.
And also look at Paris. A far greater tourist trade than London but they have no royal family. People go to Paris for the architeture, the culture, the galleries. All the things London has in abundance. Hence why our tourist trade is unreliant on the queen.