"By logging onto our test drive environment using your web browser, you will be able to experience Microsoft Dynamics NAV first hand without the need of installing it on your computer. You can explore the product on your own, or follow along guided exercises and demos."
http://www.dynamicsnavtestdrive.com/
That is pretty cool! It seems to use a ActiveX "'Virtual Server VRMC Advanced Control' from Microsoft. Anyways check it out, if you are not already familiar with NAV.