The PDL module gives standard perl the ability to COMPACTLY store and SPEEDILY manipulate the large N-dimensional data sets that are the bread and butter of scientific computing.
RTS2 is project to create an open source environment for control of a fully autonomous observatory. It is running about dozen fully autonomous observatories. Its modular design allow easily addition of new devices (to already huge supported HW list).
AstroTortilla is a wrapper around common astrophotography tools intended to automate basic tasks such as polar alignment and goto correction.
Not in active development presently.