title: hyper-card interface builder in javascript?
body: <p>I've been playing with approaches to "editable mashups" - somewhat inspired by HyperCard on the front-end, Yahoo Pipes on the backend.</p>
  
  <p>There are some nice tools for "plumbing" dataflows - deri pipes being the most complete.</p>
  
  <p>What I'm wondering is if there are any interface builders, or js libraries, that run completely in a browser window - the way that HyperCard let one simply go into "edit mode," then drag and drop interface elements (buttons, fields, widgets) on the page; link those elements to code; and end up with a fully functional web page? </p>