I can't see it being useful, and it is nothing like a spreadsheet, but it is truly amazing. Thank you for doing new things.
Author here. This was a scratch-an-itch project. I often run Excel to do some quick crunching of lists and data without saving anything - text processing, find-and-replace, script generation, stuff like that. I often find that the data I'm working with fits a collection model better than a row/column model.
I am hoping the usefulness demonstrates itself over time. Glad you found it cool. :)