Baritone ukuleles

The baritone is the outlier of the four sizes. It is tuned lower, to DGBE, which is the same set of intervals as the top four strings of a guitar. A guitarist can pick one up and play it correctly within about ninety seconds, because every chord shape they already know still holds.

The trade is that it no longer sounds much like a ukulele. It is warmer and closer to a small parlour guitar, and it will not produce the bright reentrant chime of a soprano. If you want the classic sound, look at the smaller sizes. If you play guitar and want something small to keep by the sofa, this is the shortest route there.