I am just diving into working with APIs and came across API Spreadsheets. I see a huge potential in prototyping Saas ideas with it!
I believe it could also do wonders for webshop owners who wants an easy way to add new products and have them automatically imported. Havn't tested that though.

It has been amazing for me to quickly make APIs to play around with and even making a small tool for my girlfriend to help her collect data for her masters thesis.

It's fairly easy to use and understand, and the included code examples makes it really fast to work with. Overall very satisfied. Hope you stick around for a long time!