Making code writing video recordings become more and more popular.
I was inspired by great presentation by Tero Parviainen at NG-NL 2015, he made all his talk based on a coding screencast. It is something in between boring slides with ready code and life coding that takes much time.
For front-end code next step could be the option to record not only code typing but also browser output(with livereload), maybe also with opened console.
It should be nice service to make awesome coding presentation and save a lot of time!