Today's 50% off Deal of the Day from O'Reilly is Developer's Guide to Collections in Microsoft® .NET
"Put .NET collections to work—and manage issues with GUI data binding, threading, data querying, and storage. Led by a data collection expert, you'll gain task-oriented guidance, exercises, and extensive code samples to tackle common problems and improve application performance. This one-stop reference is designed for experienced Microsoft Visual Basic® and C# developers—whether you’re already using collections or just starting out."
I am looking forward to reviewing this book.