Berkeley DB (libdb) is a programmatic toolkit that provides embedded database support for both traditional and client/server applications. It includes b+tree, queue, extended linear hashing, fixed, and variable-length record access methods, transactions, locking, logging, shared memory caching, database recovery, and replication for highly available systems. DB supports C, C++, C#, Java, PHP, and Perl APIs. It supports key-value pair (NoSQL), SQL, and Java Object formatted data. It is available for a wide variety of Unix platforms as well as QNX, Android, Mac OS X, and several varieties of Windows.
BRL-CAD is a powerful constructive solid geometry solid modeling system that includes an interactive geometry editor, ray-tracing support for rendering and geometric analysis, path-tracing for realistic image synthesis, network distributed framebuffer support, and image and signal-processing tools.
IRRToolSet is a set of policy analysis tools, written in C++. It's designed to run under UNIX, using Tcl/Tk for graphics. There are tools for generating router configuration files, displaying and checking routes, generating aggregations of networks, etc. This project was formerly known as the Routing Arbiter ToolSet (RAToolset), and was maintained by ISI.
The pilot-link suite of tools contains a robust library and a series of conduits for moving information between your desktop or workstation and your Palm handheld device, such as those made by Palm, Sony, Handspring, Handera, and others. It also includes language bindings for languages such as Perl, Python, and Java.
The GOBLIN project consists of a C++ class library for a large series of graph optimization problems, GOSH, an extension of the Tcl/Tk scripting language to graph objects, and GOBLET, a graphical user interface to the library functions. GOBLET includes a graph editor and supports the standard graph layout methods.
xmmstcl lets you control XMMS playback, skip, pause, change the playlist, change skins, and do everything else provided by the xmms_remote_* methods, which is almost everything from the standard user interface. It also has some things not available there, such as "XMMS onchange" which lets your Tcl/Tk application know when something happens in the player. The companion "TkPlayer" has samples for the most important functions and will keep XMMS busy by generating random playlists with songs that you haven't heard in a while.
OpenIsis provides a library and tools to access CDS/ISIS databases, which are mostly used for bibliographic data (ISO2709, Z39.50) but also well suited for other catalogues due to the very flexible indexing mechanism. Based on a C library, there are also bindings for Perl and Java (Tcl to come).
SnackAmp is a multi-platform audio file and streaming music (MP3,Ogg, wav, etc.) player and file organizer suitable for very large music collections. Stand alone executables for Windows or Linux are available for download. An integrated Web server provides the ability to remote control the client and serve your music collection as streaming audio.
biki is a user-level keyboard layout fixup and switching program for the Linux console and X11. The standard English and Hungarian layouts with the Euro key are supported. An X11 GUI interface is provided (using TCL/Tk Wish). biki sets all keys and modifiers properly, so it can be used to fix a screwed-up layout.