From southern Namibia Crassula ausensis ssp. titanopsis is an interesting plant with tiny textured leaves reminiscent of some Aloinopsis and Titanopsis. Grown in good light the leaves can turn reddish and in time the plant forms a mat of foliage. Flower stalks appear in late summer or fall and the tiny flowers are white.
     I can't remember where I got this, maybe Tohono Chul Park. Below are pictures of mine flowering in October. Tiny flowers barely an 8th inch across.

Flower stalks in October

Flowers starting to open

Closeup of one cluster