Well, it finally happened: Tapped the blade against a mug, and dinged it. Here's how I fixed it:

If the ding is not enormous, odds are you haven't broken a chip out of the edge, you've just bent it over. Look at it closely, feel it. Is this the case? Now, we all know improper stropping can roll an edge, so why not try stropping to unroll part of the edge?

Start on the linen side. Apply some pressure, and strop for a good 50 laps or more. Examine your work. You may have to wipe dust away from the ding to see well - the curled lip of the ding sticks out and is dragging against the strop. That's good. Keep working until you see no further progress being made.

Before you repeat on the leather side, be sure you aren't using your Tony Miller red latigo or other strop that you want to keep looking pristine. Use your starter strop that you nicked up. The curled lip we want to unroll will drag against the leather a lot harder than a smooth blade. It shouldn't leave deep scratches if you worked it on the linen side enough, but you will see some evidence of wear. You can think of this as antiquing, or you can use a different strop. Again, strop 50+ laps with pressure, wipe the dust away from the ding, and check it. Repeat until you see no further progress being made.

You can't completely repair the blade this way, but you can save yourself a lot of honing. I was able to reduce the ding in my blade from nearly half the length of the bevel (it's a full hollow) to some small fraction of a millimeter. This was a lot less work than honing the entire edge down to meet the ding.