Just stumbled across Storm. Similar to Hadoop and useful to distributed computations.
Storm is a distributed realtime computation system. Similar to how Hadoop provides a set of general primitives for doing batch processing, Storm provides a set of general primitives for doing realtime computation. (via https://github.com/nathanmarz/storm)
A Storm cluster is superficially similar to a Hadoop cluster. Whereas on Hadoop you run “MapReduce jobs”, on Storm you run “topologies”. “Jobs” and “topologies” themselves are very different — one key difference is that a MapReduce job eventually finishes, whereas a topology processes messages forever (or until you kill it). (via https://github.com/nathanmarz/storm/wiki/Tutorial)