Stampede Jerusalem Artichoke (Helianthus tuberosus). This variety is said to have many virtues: it only gets about 5' tall (maybe won't need staking?), is very productive (10 pounds of tubers from 1 plant), ripens early (in September), and hardy to -30 °F (not that I EVER want to experience that!). Now if only I can keep track of them and pull out only last year's!