Whether you spell it with an `s' or a `z', digitisation and online access is the latest trend in medieval manuscripts. I work on a project called Parker on the Web, which will put every page of every manuscript in the Parker Library (Corpus Christi College, Cambridge) on the internet.
Digitisation is still a relatively new field and this page will offer some links, hints and general reviews of equipment.
Here are some pages with information on digitisation:
The digitisation of medieval manuscripts requires special equipment, which falls into three general categories:
Digitisation Bibliography
List of Manuscript Digitisation Websites
King's Digital Consultancy Services