Anyway, I accidentally broke it with an OpenWRT update that went badly. I did not want to have to create a Jtag for it, if I could avoid it. I tried a 30/30/30 reset. That failed. The router would power on and the DMZ light would turn on for five seconds and then turn off. This continued indefinitely.
After looking it, up it appeared that the boot loader was working, but that the firmware image was missing or corrupt. I followed the advice I found on several locations:
Attempt to push the stock Linksys firmware to the device using TFTP. It looked like the simplest way to do that would be to use the DrayTek Vigor router tools. Specifically, I used their "firmware upgrade utility." It worked on the first try. It's a simple process:
I later installed DD-WRT using the built-in Linksys firmware update page. DD-WRT. I could have used Tomato or OpenWRT again, but I wanted to try out DD-WRT. I'll likely write a post or two about my experience with DD-WRT.