A nicer numpy
Numpy is a widely-used tool for numerical computation in Python. Despite its wide reach, some of its core functionality is opaque, and in need of improvement. I will describe two libraries that aim to make numpy much more pleasant:
"numpysane" provides facilities for reasonable manipulation of dimensions, array concatenation and broadcasting (in both Python and in C).
"gnuplotlib" is a plotting library with gnuplot as the backend. It is fast, has a nice API, and produces the same plots as non-Python-based tools.