I love Fish, I've found it super easy to write small helper utilites for working with virtualenvs or opening Sublime projects. The barrier to scripting is so low and the language so approachable that if I have an idea for a new function I'd like to write, I can get it working in < 10 minutes almost every time. +1 to all the comments about `abbr` for abbreviations, makes working with Git great since I can still tweak the command before if I need to before it runs, plus it helps me remember what the command actually is instead of just setting & forgetting like with an alias.