That’s really cool collection added to Expression Gallery! Have you thought about visual patterns for your Silverlight and WPF projects? It’s not only graphics or screenshots of good practices. It is a real library of XAML + code samples that demonstrate a unique visual styling for a common visual elements. You can find Pattern Library with subcategories under the list of default Expression Gallery categories. There are:

• Backgrounds and Blends
• Buttons
• Calendars and Time
• Charts, Graphs, and Gauges
• Forms and Dialogs
• Indicators
• Layout
• Lists
• More Patterns
• Navigation
• Pagination
• Ratings
• Touch and Gestures
• Transitions
• Windows Chrome

Particularly, I like these patterns:

• Zig-Zag Stack
• Analog Sweeping Clock – Silverlight
• Menu Callout Drop-down