[fulafel]

It's very good and straight to the point about transforming data. The central data structures (maps, keywords, vectors) and excellent languge + standard library centered around those, combined with interactive iteration at the REPL, make for a rewarding development experience when you can just try stuff. Since most things are immutable and passed around as data, you can easily rerun things at the REPL with high confidence that objects in your data aren't being mutated.