Jacob's ladder is a delicate little perennial with attractive fern-like foliage. It features small blueish bell-shaped flowers spring though early summer.  It is often one of my first perennials to bloom in the garden.
 
This species likes stony soil, and is a great choice for a rock garden or well-drained slope. It is not prone to spreading, and does well with other 'well-behaved' species such as alumroot, lance-leaf stonecrop, wilcox and alberta penstemons, and sticky cinquefoil. In particularly hot locations (like the valley bottom) I recommend planting in a spot with at least some protection from direct afternoon sun. 
 
It can exhibit a skunky smell, but generally only when the leaves are disturbed; I would describe it as more curious than unpleasant. (Ok I'm not going to sugarcoat this. It smells like weed. But only noticeable if you stick your face really close to the plant)