I learned today that there are naturally occurring and healthy prions in the brain. That makes sense, now that I think about it, just as there are helpful and harmful versions of the same bacteria, there can also be helpful and harmful versions of prions. These healthy prions may help prevent Alzheimer's. Also, healthy prions may function in our sense of smell.
So, I'm still not eating brains, but I won't completely write off prions as being potentially useful, at least not the healthy variety.