Visual Studio 2008/2010 Development server drop-in replacement
CassiniDev.VisualStudio is a fully compatible drop-in replacement for the Visual Studio 2008/2010 development server.
VS2008 manual installation instructions
To give it a try, simply archive and delete the original contents of C:\Program Files\Common Files\microsoft shared\DevServer\9.0 which should consist of 2 files, WebDev.WebServer.EXE and WebDev.WebServer.manifest and drop in the supplied WebDev.WebServer.EXE (CassiniDev in disguise).
You may revert to the original at any time by simply replacing the original files.
For VS2010 follow the same procedure in C:\Program Files\Common Files\microsoft shared\DevServer\10.0 using the supplied WebDev.WebServer20.EXE and WebDev.WebServer40.EXE files. (Coming soon)
Find a beta version of the executable in the list on the right of the Dowloads page.