Our invitation got lost in the Royal Post Office so this is not an original picture. (just in case you wondered)
When I searched for this example of .... I can't think of the right word, but anyway, you have to be approved in advance.
You can imagine the fun pranksters would have with the bidding. I read that is up to about $30,000 U.S. dollars so be ready.
Here is the link to see the listing and get registered. http://cgi.ebay.co.uk/Princess-Beatrice-Royal-Wedding-Hat-Philip-Treacy-/2306205...
If you search normally, you may be bombarded with similar listings and I would not want you to get confused. Here are the exact search words if you want to "Princess Beatrice Royal Wedding Hat by Philip Treacy" in case you want to find it directly.