Web Client takes a little setting up, and it also requires that the client side application is n-tier compliant , but once it is installed, it makes distributing version updates a snap. Each time a client  session starts, it checks to see that it is running the correct version - if an update is required it seamlessly downloads and installs the required code before starting the application.

If you have a progress GUI application with any more than ten users, we highly recommend you investigate this technology. Everyone we know that uses it absolutely loves it! You can't get a higher recommendation than that.