I built a CRM demo for a client the other day using Demo Builder ( http://demobuilder.cloudapp.net/ ) . This tool is such a great starting point for demo's because you get a lot of great extra's and demo data that would take you awhile to put together in your own personal organization. It also comes pre-configured with the out-of-the-box SharePoint integration already set up, along with the partner and customer portals already configured in Azure. Lots of good stuff.
I had asked a Microsoft representative when the demo builder would start building demo's on CRM 2013 and they stated sometime later in November. Evidently that came sooner than expected because it is building demo's on 2013 now. If you do the standard demo (still labeled Polaris) it will build a 2013 org with the demo elements configured..