Visual Subst

Visual Subst is a small tool that allows you to associate the most accessed directories with virtual drives. It uses the same API similar to the console 'subst' utility, but makes it easier to create and remove virtual drives in a GUI way.
For Programmers

If you have the Platform SDK installed and need to use it frequently, it is possible to create a virtual drive mounted on the Samples directory. You can therefore reduce a long path like 'C:\Program Files\Microsoft Platform SDK\Samples\Multimedia\DirectShow' to just one letter.

In my opinion, this is the shortest way to gain access to the sample source code from the SDK when it is required on a continual basis.