Comment by throwaway17_17

Chapel and Lustre (a parallel, distributed file system) from Cray were funded by DARPA’s High Productivity Computing Systems program. This work, along with Fortress, from Sun, were developed explicitly to enable and ‘simplify’ the programming of distributed “supercomputers”. The work and artifacts, along with the published documentation and research is of particularly high quality.

Even if you aren’t involved in HPC I’d say the concepts transfer or provide a great basis for parallel and distributed idioms and methodologies that can be adapted to existing languages or used in development of new languages.

TL;DR - Chapel is cool and if you are interested in the general subject matter (despite a different focus) Fortress, which is discontinued, should also be checked out.