Visual Subst is a cool application that allows you to create, enumerate, save and mount folders as virtual hard disk drive partitions with a drive letter in Windows Explorer. It is basically a GUI version of the SUBST command line utility.

For example, you can point C:\Documents and Settings\Username\Local Settings\Application Data to a B: drive which would show up as a separate disk partition in Windows Explorer. You can then type B: in the run dialog box or the explorer address bar and the folder will be launched for you. This is a must have application if you refer to copy and paste files between different folders on your computer a lot, for exmaple when creating projects.

Technical information:

A virtual drive is a symbolic link in the Local MS-DOS Device namespace. It is a Windows feature added for backward compatibility with old programs. Virtual drives are therefore objects of the operating system, and Visual Subst can create, enumerate and delete these objects. All local MS-DOS device names are removed when the user is logging off. To handle this issue, Visual Subst saves the list of virtual drives into an INI-file and is able to load them the next time.

Download Link