Here's a tuning that I haven't seen available before for the baritone ukulele. Sandy Weltman's site has a couple of free songs as examples of his work in CGBD "plectrum" tuning.
Sandy says on his site Sandy Weltman Music,
"I use a plectrum tuning scheme on the baritone ukelele. It works wonderfully and allows the ukelele to resonate at a deeper/warmer frequency. For more info on this tuning, please download the free pdf below (see below). Also watch the accompanying video to learn the chords in this tuning and to get a better understanding of it (also below). Included in the pdf and video is a simple song (Ain’t She Sweet) in this tuning."http://www.sandyweltmanmusic.com/aint-she-sweet---baritone.pdf
I haven't found the Ain't She Sweet video and will need to check in with Sandy to locate it.
CGBD PLECTRUM BANJO CHORD CHART
PLECTRUM BANJO CHORD BOOK (Amazon Link)