I consider myself a pretty good ASP.NET developer.  However, it doesn't matter how many times I try to do it, I can't seem to remember how each of the path functions on the Request and Page/Control objects work.  Invariably I find myself opening MSDN or tediously debugging and stepping through my code, making heavy use of the Command Window or the Quick Watch dialog.

Thanks to Rick Strahl for consolidating these functions in a manner that's easy to read and understand.