Pediocactus knowltonii is an evergreen cactus / succulent with blue and green foliage. In spring pink flowers emerge. Features fuzzy texture. Grows well with sun - mostly shade and low water. Prefers to be dry in winter. Does well in gritty and well-drained soil. A good option if you're seeking something verticillium wilt resistant.
One of the smallest cacti in the world, only one or two inches tall, slowly forming offsets. Flowers are pale pink and quite large for the size of the plant. Currently only known from two small populations in the wild. These are seed grown, and keeping them in cultivation is good insurance against the tiny wild populations being destroyed. Experiences very cold winters in the wild, it might prove hardy with very good drainage. Zone 5, maybe?