Following my last post about LINQ, Expression Trees & Lambda Expressions I've found this Linq Quiz:
C# 3.0 in a nutshell - LINQ Quiz
Try yourself to see what your is your level and where you can get if you read\code more of this stuff (tip: C# 3.0 in a nutshell is a great book)
Enjoy.
Disclaimer The opinions expressed herein are my own personal opinions and do not represent my employer's view in any way.