Great Post from Joe
-Return of SmartPart – http://CodePlex.com/SmartPart.  The old classic from V2 days still really improves developer web part productivity.  It’s a SharePoint web part which can host any ASP.NET web user control.
-BDC Meta Man – http://www.lightningtools.com  If you are working with Business Data Catalogs, this tool is indispensible.  Yeah, I know there is definition editor that is part of the SDK, however, the free version of Meta Man blows that one away.  Even creates web parts you can customize for Create and Update operations.
-WSPBuilder http://www.codeplex.com/wspbuilder  A SharePoint Solution Package (WSP) creation tool for WSS 3.0 & MOSS 2007.  Just break out your features files into a pre-defined directory system run to gen WSPs.  No more coding manifests and DDF files.
-SharePoint Solution Installer http://www.codeplex.com/sharepointinstaller Distribute your SharePoint WSP solution files with this installation program instead of a raw script using STSADM.EXE to install and deploy the solution
-Useful SharePoint Designer Custom Workflow Activities   http://www.codeplex.com/SPDActivities – This project takes aim at making it easier to create advanced workflows using SharePoint Designer by providing a set of custom workflow actions.  Actions like Lookup User Info (eg. Lookup who a contributor works for) and Copy List Item (eg. Move doc into Records Center repository) really super-charge SPDesigner workflows.  Additionally, the code is available so if you want to create a Workflow in VS, have at it.
-SharePoint Content Deployment Wizard – http://www.codeplex.com/SPDeploymentWizard – Content is exported using the Content Migration API (PRIME) as a .cmp file (Content Migration Package) which can be copied to other servers for import. Unlike the out-of-the-box tools, the Wizard allows *granular* selection of content via a treeview.  Great way to create and import CMP files and move your content from production to test to q/a to production.