SharePoint Solution Installer is a CodePlex product that makes it easy to deploy SharePoint Solutions (.WSP files). With a simple update to the config file you can customize the way the solutions are deployed. When ready to install, double-click the Setup.exe file and the installer will walk you through the deployment of your .WSP. After some system checks it will give you a choice to do an install if this is a new deployment, or an upgrade/uninstall if the solution already exists in the environment.
It’s a simple way to save some time and also give SharePoint Solution deployments a more professional feel.