I like some stuff like Ulver's Lyckantropen Themes and Silencing the Singing. Both of those albums are good minimalistic ambient as well as Vidna Obmana's "Spore" album. I also like some minimalistic black metal such as Burzum.
hmm, i wouldn't have said that was particularly minimal really, in very small places, but not continually. most of the stuff mentioned is not fully minimal, and yeah, i would say it is the further continuum of ambient rather than an offshoot.
I've very much gotten into minimalist contemporary classical over the past year, my favorite being the works of Steve Reich.
Minimalism can pertain to many different genres, such as ambient, classical, and even some metal (Darkthrone's Transilvanian Hunger is a good example).