I've been dabbling in WPF lately. Nothing too fancy, just fixing up some parts of an application we're currently working on and integration with Reporting Services. One of the things that is quite time-consuming in WPF is layout, specially when it comes to laying out business forms (i.e. a set of fields on a form to collect data). An alternative to a writing all this by hand (or using some flavor of Expression) is to use the XAML Power Toys, which generates the XAML for you based on a series of input values.
Instead of explaining all the cool features it has here, just go to the site