Is there a way of running an ASP.NET website in a subfolder of the website?
As an example, say I wanted to run the screwturn wiki (http://www.screwturn.eu/) in a folder called "wiki" on my website, can I alter the web.config of the screwturn website to tell it that it is running in the "wiki" folder? (like saying that "~/" = "/wiki/")
The wiki would then find its assemblies that are in "~/bin" in "/wiki/bin" and the same for all other folders below the new root.
Short answer is YES you can. No need to specify the location of the folder in the Web.Config.
Piece of cake, you can either add a virtual directory to the root of the IIS website and point it at the path of your site or place it an a physical directory in the website root then turn it into an application by right-clicking on it in the IIS management console, going to properties and clicking "Create" next to application name.
I had to do this recently, and having made the wiki folder an application (as suggested in the previous answers) I also had to place a dummy 'App_Themes -> Default' folder at the top-level within the Wiki app because of the presence of the <pages styleSheetTheme="default" theme="default"> tag in the parent app's Web.config. Small hack, but that's the way I like to configure my styles in Asp.Net, and I didn't want to change that.
You need to stop the configuration inheritance in the root web.config file so that the wiki web.config doesn't read anything from the root web.config.
Details here