There are three things history will remember about Kate and William's Royal Wedding: Kate's beautiful dress, Grace Van Cutsem -- the frowning 3-year-old bridesmaid who stole the heart of everyone who was completely uninterested in the Royal Wedding, and Princess Beatrice's hat.

From the moment the world first saw the hat through the window of the car whisking Beatrice and her sister to Westminster, it was an instant hit on the Internet. Before the happy couple could exchange vows, "Princess Beatrice's ridiculous Royal Wedding hat" had 5,000 Facebook fans. By 8 p.m. EST, it had close to 44,000. Currently it has 138,870.

The hat has been compared to everything from a pretzel to a toilet seat to the eye of Sauron.

And now, the very hat that made serious Internet waves on auction for charity.

"She's putting it up on eBay to auction it for UNICEF and for Children in Crisis," Beatrice's mother, Duchess Sarah Ferguson, announced Wednesday during an appearance on The Oprah Winfrey Show.

Those interested in the blush-colored topper -- originally designed by renowned London milliner Philip Treacy -- have until 22 May, 2011 to place their bids. The current price? About $8,620.

Philip Treacy hats typically cost about $3,300.

What would you do with the hat if you won the eBay auction?

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