I've spent time using alum/salt several times, on coyotes and once on a deer hide. Tried the brain/ash method once as well. Interesting experience, but not one I will repeat without a really good reason. Lots of work "breaking" the hide to soften it.
Paid for a couple to be professionally done, and even bought a couple tanned hides from private individuals. Right now I am experimenting with a quick-tan kit from Van Dykes and have high hopes for it; definitely the lazy man's route to a tanned skin, if it works. Fingers crossed.