[nnq]

If you're asking yourself what kinds of problems is a Lisp good for you should probably watch this: https://www.youtube.com/watch?v=8X69_42Mj-g (A computational chemist built himself his own Common Lisp implementation because no other language available was powerful enough for his needs...)

It basically boils to: if you're solving a truly new and interesting problems for which the current libraries and ecosystems don't matter that much to you anyhow (because what you do is too bleeding-edge / ahead of everyone else, so you'll write your own better stuff anyhow), than you might want to choose a Lisp.

And if your problem is so bleeding-edge and exotic that you also need to build your own programming-language for it, than you might just as well build yourself a Lisp (like the guy in the video did) and add your needed features to it, because this would be easier than any other approaches and allow you to spend more time on your problem and not on the language...

EDIT+: another example is DWave using SBCL: http://www.dwavesys.com/careers/senior-software-developer - if quantum (or analog... anyway...) computing is not "truly new and cutting edge", than I don't know what is