C++ has some language constructs that are rarely seen in use. These constructs have their own, valid uses, but should be used sparingly. As the now adage-status quote from The Old New Thing says:
In this series we will take a look at different instances of unusual C++ language constructs, shortly explaining their use-cases, syntax and pitfalls.
UPDATE: the series was moved to Dr. Dobbs! The rewritten, expanded first part is available here.