How to Bind Slider's Thumbnail size change to its value

Question

I would like to know how can I use xaml code without extantional code?

I want to create a Slider, that its Thumbnail change its size while moving up or down the slider's value.

We know that we can use C# Converter is there a way to do that using xaml only.

Thanks.

ScreenShot [URL=http://img69.imageshack.us/i/wpfbind.jpg/][IMG]http://img69.imageshack.us/img69/2691/wpfbind.jpg[/IMG][/URL]