libmikmod is a portable sound library, which used to be packaged with the MikMod module player, but is now released independently. It is capable of playing samples as well as module files, using the OSS driver for output, as well as ALSA and EsounD. Supported module formats include MOD, S3M, XM, IT, MED, MTM, and 669, to name a few.
Groonga is a fast and accurate full text search engine based on an inverted index. Newly registered document instantly appears in search results, and updates are allowed without read locks. These characteristics result in superior performance for real-time applications. It is also a column-oriented database management system (DBMS). Compared with well-known row-oriented systems, such as MySQL and PostgreSQL, column-oriented systems are more suited for aggregate queries.
MathGL is a library for making high-quality scientific graphics under Linux and Windows, fast data plotting and handling of large data arrays, working in window and console modes, and easily embedding into other programs. It has more than 40 general types of graphics for 1d, 2d, and 3d data arrays. It can export graphics to raster and vector (EPS or SVG) formats. It has an OpenGL interface and can be used from console programs. It has functions for data handling and MGL language scripting for simplification of data plotting. It has several types of transparency and smoothed lightning, vector fonts and TeX-like formula drawing, an arbitrary curvilinear coordinate system, and many other useful things.
Calligra is an integrated suite of applications that cover office, creative, and management needs. It offers applications on both desktop computers and mobile platforms like tablets and smartphones. OpenDocument Format (ODF) is used, making it compatible with OpenOffice.org, LibreOffice, and Microsoft Office. Calligra Suite contains the following applications: Calligra Words (word processor), Sheets (spreadsheets), Stage (presentations), Flow (diagrams and flowcharts), Kexi (visual database creator), Braindump (note taking), Plan (project management), Krita (drawing), and Karbon (vector graphics).
SQLObject is an object-relational mapper, i.e., a library that will wrap your database tables in Python classes and your rows in Python instances. It currently supports MySQL through the 'MySQLdb' package, PostgreSQL through the 'psycopg' package, SQLite, Firebird, MaxDB (SAP DB), MS SQL, and Sybase. It should support Python versions back to 2.4.
v4l-utils is a collection of various video4linux (V4L) and DVB utilities. libv4l is an accompanying collection of libraries that adds a thin abstraction layer on top of video4linux2 (V4L2) devices. The purpose of this layer is to make it easy for application writers to support a wide variety of devices without having to write separate code for different devices in the same class. It consists of 3 different libraries. libv4lconvert offers functions to convert from any (known) pixel format to V4l2_PIX_FMT_BGR24 or V4l2_PIX_FMT_YUV420. libv4l1 offers the (deprecated) v4l1 API on top of v4l2 devices, independent of the drivers for those devices supporting v4l1 compatibility (which many v4l2 drivers do not). libv4l2 offers the v4l2 API on top of v4l2 devices, while adding support for the application transparent libv4lconvert conversion where necessary.