IFrames are a powerful extension tool within Microsoft Dynamics CRM 4.0. In addition to allowing you to host custom websites, IFrames allow you to present relevant data from external websites within the context of an open entity. As a quick example, this blog post will show how to present historical information regarding a company’s stock price from within an account form. I hope this example will inspire you to find many other ways to present relevant data to users through the use of IFrames.