lxml is a Python binding for the libxml2 and libxslt XML processing libraries. It aims at ease of use of the API for Python programmers and exposing the many libxml2 features. It implements the Python ElementTree API on top of libxml2. It extends this with support for XPath, XSLT, Relax NG, XML schema, and more.
m3ute2 is a CLI program designed for easily moving subsets of large media collections from one location to another while providing information to the user about what it is doing. It can take file data from both lists (text files such as M3U playlists and plain lists) and directories, with powerful filtering options for both.
MacSTL is a C++ source library which offers an implementation of std::valarray which is optimized for the SIMD instructions on PowerPC and Pentium processors. It runs from 3.6 to 16.2 times faster than hand-coded scalar loops. It also wraps the SIMD data types in an object-oriented package, allowing programmers to use familiar infix notation (e.g. v0 = v1 + v2).