My craft + tech startup www.youpatch.com uses Racket for the clever bits: image-processing, pdf generation, and I find it's great for prototyping and R&D. Here's my talk wide-ranging talk about it (video and slides) http://agile-jitsu.blogspot.com.au/2015/01/my-talk-at-racket...

Also at RacketCon 2014 Brian Masterbrook talked about using Racket at www.airstash.com for testing hardware: links at con.racket-lang.org

Dan Liebgold (Naughty Dog) at RacketCon 2013.

"Racket on the Playstation 3? It's Not What you Think!"

https://www.youtube.com/watch?v=oSmqbnhHp1c

Racket is the runtime powering HN. Arc targets it.

I use Racket to run an internal website for few hundreds of T.A. in my department in the university. I like that everything is escaped automatically, so you don't have to worry that someone try to use "<script>alert('test');</script>" as name.