Why #Haskell ? Thread.
It's such a different way of thinking fundamentally due to the alfonzo/turing split and this has lead to unique features that slowly bleed into the general language ecosystem. One of my favorite features of Haskell is exactness and correctness. The type system lends itself to not just catching the kind of errors that would be normally runtime errors in some other languages, but it it also lends itself to things like formal verification and proof assistants like...