Eileen has blogged on PPtPlex that has come out of MSR. As she mentions I heard about it first from a customer who presented at our UK company conference last week. He certainly made good use of it. I've not had must time to use it, other than just install it, but Eileen's got a good explanation and a few screengrabs here. If you present a lot, or use PowerPoint a lot then give it a go...

Eileen Brown's WebLog : PptPlex changing the way you present