Sure, check out pgloader (this guy re-wrote a Python program into Common Lisp and wrote about the experience), the European Lisp Symposium ( http://www.european-lisp-symposium.org/content-programme-ful... ), it's used by Google (ITA, air fairing system), it was used by Naughty Dog for their PS1 and PS2 games (they still use Lisp for scripting), it's been used by NASA, DART ( https://en.wikipedia.org/wiki/Dynamic_Analysis_and_Replannin... ), Cyc, there's a European company I can't remember the name of that uses Common Lisp for its train scheduling system. There's this new Swedish music company that uses Common Lisp for their software.

If you want to see much used applications in the Common Lisp community then check out all of Edi Weitz' software http://weitz.de/

Most Common Lisp that you use is in stuff you don't see, there're no Ruby hipsters here.

EDIT: Oh, or why not something like StumpWm? Really, thre's a lot of cool Common Lisp software out there.

Lisp was popular back when the "interesting" apps were things like compilers, AI systems, mathematics systems, GUI's, etc. See: http://en.m.wikipedia.org/wiki/Category:Common_Lisp_software

It's a bummer compilers out of vogue now. For example, lackluster compiler tech is the reason GPU computing is still stuck in rare niches.

what do you consider interesting nowadays?

I mean "interesting" in the sense that those were areas of active research and development. I think the equivalent today would be things like control software for self-driving cars and drones, the software that does StreetView, etc.

Not on github, but, IIRC, Catia is written mostly in Lisp.

You're probably thinking of AutoCAD, which isn't written in Lisp, but scriptable using Autodesk's variant of Lisp.

Yes, it was PTC. I couldn't remember it. Thanks.

StumpWM window manager, the successor to Ratpoison. Both are awesome (obvious disclaimer: I use both).

Not on Github per se, but still awesome.

StumpWM is on github. https://github.com/stumpwm/stumpwm