We used jQuery UI as a framework, but built a lot of custom widgets for the wires, modules, nodes, receptors, etc. Yahoo Pipes was certainly an inspiration for our design, but we rethought the concepts behind using wires (using them as a control flow mechanism, not a data flow mechanism; e.g., there are no wires for variables, we use them in sort of the way MIT's Scratch does).

We don't know of any framework for this sort of interface, and we did not want to use Flash, so we just rolled up our sleeves and made it ourselves. jQuery and jQuery UI, however, were instrumental; for this sort of new-ish UI, it was useful to have the ability to progressively layer functionality onto HTML elements. We also made extensive use of the $.Widget framework to construct our widgets in the same fashion as jQuery UI's.

Neyric's javascript wiring library is inspired by Yahoo Pipes.

http://javascript.neyric.com/wireit/guide.html