I've recently started working with SharePoint 2007 and needed to create my first WebPart. The purpose of the WebPart was simply to allow a user to connect to an external ASP.Net 2.0 application and allow a direct pass through for the current SharePoint user, simulating a single sign on experience. After a doing a bit of research and analyzing the needs it was decided to keep it as simple as possible. A simple LinkButton with an event to do a Response.Redirect to the required URL and adding the Username to QueryString. The directed application will take care of the login...