When flipping through Maurits Smeyers, Flemish Miniatures from the 8th to the Mid-16th Century, after acquiring it, I found a plate which made me go immediately "I want to adapt that for a Silver Guard":
Not too long after that, Trin signed me up for a Silver Guard on the backlog, and I set out making the adaptation.
It turned out to be both more difficult and easier than I expected. It was easier to come up with a workable wording than I would have thought, but it was harder to decide exactly what colors and what media to use. With the exception of the letters and the gold, all the rest is ink, instead of paint, and I generally used a pen with a very fine nib, rather than a paintbrush. I'm not entirely happy with how the color for the tunic turned out, my guy's face looks rather bizarre compared to the original (and Joel says his hairdo looks like a Pharaonic headdress), and I didn't get the spacing quite right (notice the unfortunately rather small bottom margin, and the lack of the outer border, which I think finishes off the original nicely but which I didn't have space for on mine) but overall I'm pretty happy with how it turned out:
What I most love about this design is how totally different it is from any other illumination I've ever seen.
EDIT: My friends on LJ know some cool stuff. It appears that the plate reproduced in Smeyers is itself a copy of an earlier, 9th C, manuscript, and that the person depicted is Louis the Pious. Here's a picture of that plate, courtesy of Wikipedia.
Knowing that mine is a copy of a copy of an image makes it even cooler.