I found the last time I taught that working out a general outline for lectures and then going to look for pictures for PowerPoint (or whatever presentation software) is often really helpful in getting my own brain in gear for teaching. So, I tend to go type a few phrases in to Google Image Search and see what turns up. This is also immensely helpful in shutting up the little voice in my head screaming "how on Earth are you going to illustrate *that*?" which sends me into fetal-position procrastination. Because if I don't work on it at all, somehow that will make it less scary.
Seriously, brains are stupid sometimes.
Anywho, as is often the case with the wonder that is the internets, I inevitably find things that are interesting but not of immediate use. Like this link:
Project Grant Report | Byzantine Studies | Research | Dumbarton Oaks
Kiln furniture!!! And fabulous incised sherds. And those are the wasters - stuff that got chucked after the first firing because it didn't come out quite right.