In case others want to try it out and don't know how to get clockwork mod installed:
Download
Rom Manager from the market and then follow
these instructions starting from the second image. It used to be that the market Rom Manager didn't know about the Nook Color clockworkmod image, but now it does, so no need to manually install Rom Manager or download clockworkmod separately (Rom Manager will do it for you).
Note that if you do this you will no longer be able to reset your device using the 8-failed reboots. Your only recovery will be through either 1, clockwork recovery or 2, booting off of the SD card (say, using Nookie Froyo) and fixing it from there (dd-ing a good image or even just putting back the BN recovery).
Clockwork is a replacement for the BN recovery method with more features, including making full system level backups of your device (nandroid backups).