I have been kicking tires using vim and
lein repl for the past couple days but this morning I decided to take it to the next level.
I finally watched Rich Hickey's Keynote: The Value of Values. This doesn't help with Clojure directly but it really helps to get clear on what a value is and what it isn't and why you want your software to work with values. Really worth a watch and it will challenge the way you look at code and data.
After watching this video, I set about trying to get a decent dev environment setup so that I can experiment with the code without having to repaste into a REPL. For me, the best way is to get a solid IDE setup and use unit tests for the tire kicking. RubyMine has been really good for me, and I decided to use IntelliJ CE with the Cursive plugin. There's still a good bit of configuring you need to do and it doesn't fully feel native but it was better than my feeble attempts at using Eclipse.
Thank you to JetBrains and Ideogram for making non-commercial versions available.