I ran across this in a Google search. Eric Granata built this digital signage solution for his church and it looks great! Basically, he is pulling from multiple data sources, combining them and formatting them through a custom Flash Projector.
He shows a mac mini and a mac cinema display in his graphic, but you could achieve the same thing with a cheap PC (which he mentions) and a cheap monitor or cheap projector.
I love the idea, and it is right along the lines of the kind of topic we want to talk about at GR.