Whatever I feel like it. Just like any general purpose programming language.
If you really want to see what the industry uses it for, here's some examples:
http://wiki.alu.org/Industry%20Application
http://wiki.alu.org/Success%20Stories
However, I only care about the language's strength for my own usage. I use a language if it provides me with the features I need, and there are good implementations and libraries. CL happens to be one such language, so I use it, no further requirements are needed here.