I personally like Pink Moon the best, there's just something about that album that I can listen to it over and over again.

I always break out Nick Drake around November/December...just always in the mood for him around that time of year for some reason.

Not sure what my favorite "folk" album is, but I'll list Beck's Sea Change because that album may be my favorite 'sounding' album.

Something about the engineering and the mixing on that album that draws me in.