A company called Bee Mobile has created a series of controls for Windows Phone 7, called Metropolis. I was searching for a Book control and this controls' suite has one, so it has been immediately impressive to me.
I have been playing with the trial, and I had a chance of taking a look at the available controls, which are the following:
- BookControl
- iWheel, which allows implementing rotations of objects and creating stuff like a date or time picker
- RegionControl
- VistaButton
- WaitingBar
It is worth mentioning that the setup also installs a sample solution to show how to use all controls, however here you find a number of figures about some of them:
RegionControl, which allows selecting specified areas over a content, in this case the human body representation:

WaitingBar, a nice replacement for the built-in progress bar:

A date picker built with the iWheel, to select dates:

This is my favorite, the BookControl, which allows browsing XAML visual elements as if they ware pages of a book:

All controls are easy to use. As an example, here is how you can populate a BookControl:
<my1:BookControl Name="bookControl1" HandleSize="120" Margin="-12,0">
<Canvas Width="362" Height="478">
<Canvas.Background>
<ImageBrush ImageSource="/MetropolisSample;component/Images/catStart.png" />
</Canvas.Background>
</Canvas>
<Canvas Width="362" Height="478">
<Canvas.Background>
<ImageBrush ImageSource="/MetropolisSample;component/Images/france.png" />
</Canvas.Background>
</Canvas>
</my1:BookControl>
As you can see the Canvas panels (and their visual tree) are the page contents.
I would definitely recommend this suite of controls because it is easy to use and has controls that you will not find elsewhere.
Alessandro