Sharing ASP.NET User Controls across Pages

We recently published a How-To on support.microsoft.com for
how to share user controls across projects.  In talking with customers, one of
the things they would like to do is have a common set of reusable web UI, say a navigation
bar, across multiple Visual Studio projects.  The problem is that there hasn't
been an easy way to do this, and creating a server control seems like a lot of work
for something so simple.  To help make this easier, this article gives
step-by-step instructions for creating a virtual directory for common user controls
that can be reused in multiple Visual Studio projects.