This is incredibly useful, a lot of my peers will certainly love it for quick prototyping data manipulation and exploration. I know I will. This is a very clever/usable implementation of flow-based programming (FBP), which is dear to many people's heart in HN and out. FBP matches very easily the mental model of data flow and calls for quick mouse- or touch-based manipulation. Coming up with a usable UX for such parad…
For interested readers there is a decent article[0] and previous discussion[1] a few months back which discusses this topic.