How do you clear your MRU list in Visual Studio?

There is an MSDN article here which suggests that you just move the projects to a new directory.

However, as you mentioned, the list of projects is kept in the registry under this key:

HKEY_CURRENT_USER\Software\Microsoft\VisualStudio\<version>\ProjectMRUList

and the list of recent files is kept in this key:

HKEY_CURRENT_USER\Software\Microsoft\VisualStudio\<version>\FILEMRUList

Note For Visual Studio 2015:
The location has changed. You can check out this answer for details.

Some people have automated clearing this registry key with their own tools:
Visual Studio Most Recent Files Utility
Add-in for cleaning Visual Studio 2008 MRU Projects list

PowerCommands for Visual Studio 2008

Features

• Clear Recent File List
• Clear Recent Project List
• Clear All Panes
• Copy Path
• Email CodeSnippet
• Insert Guid Attribute
• Show All Files
• Undo Close
• Collapse Projects
• Copy Class
• Paste Class
• Copy References
• Paste References
• Copy As Project Reference
• Edit Project File
• Open Containing Folder
• Open Command Prompt
• Unload Projects
• Reload Projects
• Remove and Sort Usings
• Extract Constant
• Transform Templates
• Close All

If you try opening up a project that can no longer be found, Visual Studio will prompt you for permission to remove it from the MRU list. So if you temporarily rename an appropriate top level folder to fake the projects' disappearance, you can get rid of the projects one by one.

I found the MRU editor from Code Project a great tool for that. No problems with it, and it works on 2003, 2005, and 2008.

I had this issue as applied to VS 2017 where you do not have any MRU items in the registry as in the previous versions. The solution was, on the other hand, simple: go to "Tools->Extensions and Updates" and install "Power Commands for Visual Studio". After they have been installed, your File menu will look as shown below.

Just click the menu item to clear the project MRU.