Spotlight is also amazing, but like Preview I suppose it doesn't count as a hidden gem. Finder's column view is also excellent. I think it's the best way to na

Spotlight is also amazing, but like Preview I suppose it doesn't count as a hidden gem. Finder's column view is also excellent. I think it's the best way to navigate the filesystem through GUI; the way it displays nested directories is just super nice. It makes me wonder why other OS don't haven't copied this layout in their filesystem explorer. Grapher.app is also perhaps a hidden gem.