Nobody's mentioned Julia?! I love this language. I do scientific research and high performance computing and have been exploring this language extensively over

Nobody's mentioned Julia?! I love this language. I do scientific research and high performance computing and have been exploring this language extensively over the past year. Combined with something like iJulia (iPython), it's a very versatile tool for analyzing and processing data. It's got a few quirks, but the language designers are improving it rapidly and the number of libraries available for it is increasing drastically. To name a few features I really like about the language: multiple dispatch, flexible type system (use it if you need performance; ignore it if you want pretty code), powerful macro system, extensive debugging system (instantly view AST, LLVM, and native assembly output to optimize), easy parallelizability/vectorization, and just an overall beautiful language design (unlike C++ or Matlab for instance). Things I dislike about Julia, but that should be changed soon: unintuitive automatic memory allocations (everything seems to allocate new memory by default which is a pain for tight loops because you have to write layers of functions that all take tons of "output variable" parameters), incredibly slow start-up times, and documentation that leaves a lot to be desired in terms of details (I normally have to call methods() in a REPL to figure out exactly what I need to pass into functions). Also, the module system seems a little more confusing than it needs to be.