Yahoo pipes was obviously influenced by UNIX pipes and as such is one of the best demonstrations of flow based programming to date. I really loved Yahoo pipes and it influenced the way I think.

Pipes was a basic web "agent". It made basic programming available to the everyman much like HyperCard. Perhaps is just needed a runtime UI that matched the excellence of its design time interface.

Yahoo is focussing on mobile yet here they had this custom agent building tool that could easily be re-purposed to mobile to make a killer platform for Yahoo users.

Hopefully they will opensource the first generation perl version.

Some of my favourite flow based programming links follow.

Surprised nobody has mentioned noflow node.js workflows:

  https://github.com/noflo/noflo

Also this (untested) will convert your yahoo pipes into Node.js

  https://github.com/neyric/pipes2js

and this one (also untested) will do the same in python:

  https://github.com/ggaughan/pipe2py

There is also python pypes which has a yahoo pipes like frontend with a stackless based backend.

  http://pyvideo.org/video/400/pycon-2011--large-scale-data-conditioning--amp--p
  https://github.com/fullscale/pypes

Other python flow based programming tools

  https://wiki.python.org/moin/FlowBasedProgramming
  http://www.kamaelia.org/Home.html (BBC research)
  http://www.ruffus.org.uk/index.html

Wireit is a javascript pipes like frontend

  http://neyric.github.io/wireit/docs/

As you can see I loved pipes and I can