If you're obsessed with ancient ways of killing people and destroying cities, then Happy Holidays! The good folks at the British Library have a present for you: They've digitized Burney MS 69, a collection of Greek manuscripts on siege engines and other modes of making war. The documents range from Hellenistic engineers to Byzantine generals. Of course, they're written in Greek of various ages (so sucks to be me and probably you) but they also include illustrations. He-he.
This is part of a larger digitization of Byzantine manuscripts that include sermons, hymns, prayerbooks, letters, and an "Historium Romanae" by Appian.