I'm a big fan of Yahoo Pipes, and sad to hear it's being shut down. Pipes and Visual Basic shaped my view of how fun and easy programming can be.
We're trying to build on this legacy with Weld(.io). See a sneak peek of our programming UI at 0:40 here: http://youtu.be/faG3uuOnqxY
If anyone in the Pipes team would like to be involved somehow, ping me on tom@weld.io