One of the most compelling projects out there, active since 2010, focusing on the early modern period:
republicofletters.stanford.edu
“Mapping the Republic of Letters is a collaborative, interdisciplinary, and international project in the digital humanities, centered at Stanford University. Since 2008, we have been creating visualizations to analyze “big data” relating to the world of early-modern scholars. We focus primarily on their correspondence, travel, and social networks. While we make use of quantitative metrics to examine the scope and dimensions of our data, we remain committed to the qualitative methodologies of the humanities. We actively encourage collaborations with other projects.”
See “Digitally Mapping the Republic of Letters,” New York Times blog post from November 16, 2010 and “Digital Keys for Unlocking the Humanities’ Riches,” an accompanying piece published also by the New York Times, November 16, 2010
Case study: The Grand Tour