R17 - flexible, scalable, relational data mining language. Looks quite interesting, basically something like a cross between AWK and SQL. The result isn't really pretty, but it seems practical - especially because you can easily use multiple processors, or even multiple machines (implicit parallelization), and thus also quite easily evaluate large amounts of data with ad-hoc queries. Because there is a simple format for passing data to further steps, it can also be easily adapted to new data sources without first running a lengthy export step there.