Hidden features of Clojure (here, via @citizen428) -- This is a thread at Stack Overflow. Please contribute if you know of any other hidden feats.
Clojure's answer to named-args, a 1-line change (here, via @fogus) -- "added support for associative destrucuring for seqs by pouring them into a map first, thus supporting associative destruring of & args".... so that.
Computing with units and dimensions (here, via @sldfjd) -- This is a very in-depth article on how to make calculations with units in clojure using clj-units. The article is written by the same author of the library and it explains how to use and some of its internals.
labrepl, making #clojure more accessible (here, via @wmacgyver) -- @sutarthalloway offers his latest creation, labrepl, to the clojure community. Labrepl is an aid tool for teaching clojure. He also asks for the community to give back by providing support for currently-unsupported IDEs.
Clojure's Mini-languages (here, via @fogus) -- A very interesting article about the many different mini-languages that exist in Clojure, from the destructuring language to the regexp one. A must read.
Ask HN: Help For Clojure Addiction (here, via @looselytyped) -- A well known downside to Clojure is that it is highly addictive. Someone got hooked and is now reaching out for help. Should I suggest that he does whatever this guy did?