I write a lot of reusable components. Most recently, I created an assembly to handle notifications in various projects. For this assembly, I needed various configuration options, such as an SMTP server address. For configuration in .NET projects, we turn to App.config files, and in ASP.NET projects, we have the Web.config. In the case of a DLL however, it isn’t really advised to create/use an App.config file. On Stack Overflow, Chris Ammerman goes into great detail on the topic. But, hey, what if you want to use one anyway?