Extension methods are one of the many great new features of C# 3.0. They basically allow you to declare static methods that appear to be instance methods of a type, even if you have no access to the type (sealed classes, etc). The key point is that you...

I was doing some tests on LINQ over DataTables where I was selecting into a new anonymous type. The code was quite simple, just doing a basic select. var res = from n in contacts.Contact where n.LastName.StartsWith("L") select new {n}; ...