The smallest one that I had was 'Teeny-weeny Bikini'. Also died, but only after the squirrels dug it out of a pot last year. I've ordered another and will try to keep this one going.
But it might be important to differentiate between "smallest" and those that just fail to thrive. TWB grew quite well until it was done in. The smallest that I still have is 'Tears of Joy' - it's sort of like a real mini 'Praying Hands' and solid green. While the plant stays really small, it thrives and the clump is now4-5 inches wide.
I also have 'Cameo' but put it into the category of those that just fail to thrive. Mine has 3 leaves this year. Woohoo! That's more than last year.
Others that are growing well for me and keep very small leaves are 'Green Eyes' and 'Tiny Tears' and 'Kinbotan'.
