APL derivatives (like q) seem to have a niche use in the finance industry for processing time series data. I've played around with J (another APL derivative) and it was interesting. I could see it being useful for certain types of problems. Probably hard to use it on a large team though since it's so hard to read.

In R I often use the data.table library and the style of programming that encourages feels similar to how J made me think.