I recently came across the Shakespeare Quartos Archive. It is a digital online archive that "is a digital collection of pre-1642 editions of William Shakespeare’s plays. A cross-Atlantic collaboration has also produced an interactive interface for the detailed study of these geographically distant quartos, with full functionality for all thirty-two quarto copies of Hamlet held by participating institutions."
What’s really nice about this digital collection is the ability to download the XML, view the images, and view the HTML for each item in the archive. To check it out or learn more, click on the link below: