Mimer SQL is an SQL-based, high-performance RDBMS, targeted at mission-critical client/server environments. It offers scalable performance (including multi-processor support), and is available in all major Unix (including Linux), Windows, and OpenVMS platforms. It offers Optimistic Concurrency Control as the transaction handling method, instead of the more commonly used locking-type.
Minotaur is a generalized extension which lets you run Python scripts from Tcl, or Tcl from Perl, or any of the other combinations. Minotaur works by loading the appropriate shared library into another script language's context. So, for example, running Tcl from Python means that the Python main program imports the Minotaur extension, which in turn loads the Tcl libraries - thus Tcl becomes "embedded" into the Python runtime environment (which is similar to embedding Tcl in a normal C program). As involved as that sounds, performance is already surprisingly good, and the capability is turning out to be quite useful. Minotaur 0.1 is an alpha level release, meaning: it works, aside from a few quirks and bugs, but its API and implementation might still change in incompatible ways in future releases.