SharePoint Solution Deployer (SPSD) helps you to deploy SharePoint solution packages (.wsp) to multiple SharePoint environments. It deploys, retracts and upgrades one or more WSPs and can be extended to perform additional custom tasks in PowerShell before or afterwards. Unlike the most of the available scripts on the net, it performs all necessary prerequisite checks and post-deployment actions on all servers in the farm to assure the deployment runs smooth.
Read more at http://spsd.codeplex.com