I guess i ask this out of ignorance. I've attempted some using digital, where high ISO is usually the way to go, so I sort of figured the same here. But after I posted this thread I found some stuff on flickr such as 30-45 minute exposures with Neopan Acros 100 that looked incredible, and I've got a bunch of that (as well as Provia 400X).
Mainly scope-less. I figured I'd take my Hassy 500 CM out a clear, cold Norwegian winter night.