Over at http://www.runningreality.org we're showing changing national borders, city growth, battles, armies, ships, etc over time from 3000BC to today -- literally any day in history. We're a small project team, but as we get data filled in it shows the growth and evolution of human civilization. We're working on doing detailed battle maps now. We've done Shiloh, Cold Harbor, and just started on mapping Gettysburg.