I regularly read the writings of Tanner Llewellyn on his blog Six Water Grog. He plays the tenor banjo which is also a 4-stringed instrument but tuned GDAE. All strings are spaced in 5th's. Lanny shares a lot about his musical interests, playing a lesser known instrument, musical theory, and has a unique perspective that I feel a personal resonance to.
Tanner is a very independent spirit and prefers to play melodies over strumming chords. I prefer to fingerpick more so than playing chords. I came across his blog when he posted some music on his wife's baritone ukulele
While reading today, I came across a post which had crossed into tenor guitar and had some beautiful instruments made by Flecther Instruments, there's more, take a look: