Is it possible to add links or icons that map to external sites from the UI?

Yes, depending on your requirements, sales administrators can add deep links or mashup content to a page so that you can simply click a link or icon to go directly to the application pages or an external sites without any additional clicks or navigation.

For example, you can add deep links to a business intelligence report or to an email notification, or you can copy a URL from the Deep Links page and use it to create a link on your company website. You can embed default Workspace deep link URL patterns for the supported and custom objects to any web page as a link. Your sales and service users can go directly to the details of the corresponding record within the context of Workspace. See Configure Deep Links for Workspace for more details.

With a mashup, you can view and use an external web application without having to leave your application. For details about how to embed mashup content to a page, see Overview of Mashups.