I used Pipes as the basis of data mashup classes, with non-developers students that were mostly afraid/bored of anything related to programming.
Using Pipes, in just a few hours they would make small,
custom data apps. A typical example would be a student building a pipe gathering the weather from one source and trying to fetch the relevant clothes from a retailer with pictures and links. I had a student using the location entity extraction to geocode his favorite street art blog that cited cities in the text but didn't use rssgeo, and then output the augmented feed to a map view.
It was an eye opener for some: they could get, transform and repurpose data, and it could be fun.
Pipes wasn't without its flaws: V1 was buggy and gave us a lot of trouble when 30 students were trying to use it from the same IP, the interface was plagued by the usual issues of visual interfaces (clutter…). Some things were odd, some a little too hard for what they achieved and other were magically easy!
But at a moment when every tech company is saying that "learning to code" is important, it's sad to see a tool that had real educational value disappear.
It was a really effective tool for non-developers to learn about data markup standards, to think in term of data flows, to get introduced to the idea of a data or web API.
For this particular use in education I'm not sure there is a replacement.