Edward Tufte hosts seminars, and this 1 page report is what he was talking about this year (I don't know how much content varies from year to year).
For information density, you can't beat paper, and there's a number of things you can do to make the paper very information dense, like sparklines. He argues that in some ways, sparklines are actually typography and not charts.
With the paper report people can drill into the information they want, and ask questions from there, as well as refer back to the information during Q&A. One quote he said was "They didn't get to become your peers because they can't read fast."
He also said to not give homework. When you make these reports, you spend meeting time reading the paper. It's not something they have to do before, because everyone is busy and no one will actually read it.