AnonMap.cs

//Anonymous Mapper
//Map any object to an anonymous type

public static T AnonMap<T>(this object source, T anonType)
{
	var sourceType = source.GetType();
	var destinationType = typeof(T);
	if (!destinationType.Name.StartsWith("<>"))
		throw new ArgumentException("Destination type must be anonymous", "anonType");
	var ctor = destinationType.GetConstructors().First();
	var args = new List<object>();
	foreach (var p in ctor.GetParameters())
	{
		var foundProp = sourceType.GetProperty(p.Name);
		if (foundProp != null)
			args.Add(foundProp.GetValue(source, null));
		else if (p.ParameterType.IsValueType)
			args.Add(Activator.CreateInstance(p.ParameterType));
		else
			args.Add(null);
	}
	var instance = Activator.CreateInstance(destinationType, args.ToArray());
	return (T)instance;
}

//Usage
public void CanAnonCast()
{
	var original = GiveAnon();

	var casted = original.AnonMap(new { Name = default(string), Age = default(int) });

	Assert.AreEqual(26, casted.Age);
	Assert.AreEqual("Sweet", casted.Name);
}

private object GiveAnon()
{
	return new { Name = "Sweet", Age = 26 };
}