NoFollow links are highly beneficial, if you take Rand Fishkin's point of view (which I'd strongly recommend).
Basically a NoFollow link comes from forums, comments and other online activity which shows that not only are you purely trying to build backlinks, you're actively participating in the community.
Obviously Follow are essential for your SEO "juice", but a combination of NoFollows shows that you're not only fetching for rankings, your website actually has relevance to the wider community. You may not get a direct 1:1 benefit like a Follow link, but Google can still see the DA and PA that a NoFollow is coming from, and can index that just as readily (even if it is in a completely different way).
P.S. This is a somewhat contested opinion, so I'd add the disclaimer that this is what I think.