Portable Icq Library
Small and portable ICQ library and client written in pure Python.
More Info 
Developer: lightdruid.com
License: MIT/X Consortium License
Operating System: OS Independent
Python has a very extensive, well documented and portable module library that provides a large variety of useful functions.
Developer: devshed.com
License: Freeware
Operating System: All
Invisionix Systems' portable Instant Messenger (IRSIM) uses PHP and mySQL.
Developer: irsf
License: GNU Lesser General Public License (LGPL)
Operating System: MacOS X, OS Independent, Linux
Your own portable/invisible PC system.
Developer: Invisionix Systems
License: Freeware
Operating System: linux, windows, freebsd, osx, sun
A Java GUI library that enhances the functionality and appearance of JTable.
Developer: scientific.gr
License: Freeware
Operating System: All
mp3togo loads MP3, Ogg Vorbis, FLAC, and WAV files on to a portable MP3 player by decoding them (if required) and reencoding in a consistent lower bitrate MP3 (or Vorbis) format.
Developer: Simeon Veldstra
License: GNU General Public License (GPL)
Operating System: Linux
Xapian is an Open Source Search Engine Library, released under the GPL.
Developer: Olly Betts
License: GNU General Public License (GPL)
Operating System: All 32-bit MS Windows (95/98/NT/2000/XP), All POSIX (Linux/BSD/UNIX-like OSes), OS Portable (Source code to work with many OS platforms), OS X
An open source library for processing templates.
Developer: Viktor Kruglikov
License: GNU General Public License (GPL)
Operating System: All
A portable and cycle-accurate NES/Famicom emulator written in C++.
Developer: nestopia
License: GNU General Public License (GPL)
Operating System: 32-bit MS Windows (NT/2000/XP)
Yabause is a portable Sega Saturn emulator.
Developer: yabause.org
License: GNU General Public License (GPL)
Operating System: All 32-bit MS Windows (95/98/NT/2000/XP), All POSIX (Linux/BSD/UNIX-like OSes), FreeBSD, Linux, OS X, Sega Dreamcast
A PHP 5 library for querying game servers.
Developer: gameq
License: GNU General Public License (GPL)
Operating System: OS Independent (Written in an interpreted language)
A 3D and portable chess game with an embedded Artificial Intelligence and some pretty good graphics.
Developer: pouetchess
License: GNU General Public License (GPL)
Operating System: All 32-bit MS Windows (95/98/NT/2000/XP), OS Portable (Source code to work with many OS platforms), Linux
Defence Station Portable is a Tower Defence game targeted for the PSP.
Developer: dsp
License: GNU General Public License (GPL)
Operating System: All 32-bit MS Windows (95/98/NT/2000/XP), OS Portable (Source code to work with many OS platforms), Linux, Console-based Platforms
PHP Code Snippet Library is a multi-platform compatible script that allows you to store code lines from any language, php code snippet library include 5 pre-designed themes and doesn’t require any configuration.
Developer: PHP Code Snippet Library
License: Freeware
Operating System: All
JsHttpRequest is a library for AJAX-based script creation compatible with the popular Prototype JS library.
Developer: en.dklab.ru
License: Freeware
Operating System: All
jPDFProcess is a Java library that can read, manipulate and then save or print PDF documents.
Developer: qoppa.com
License: Freeware
Operating System: All
A PHP4 database abstraction library.
Developer: John Lim
License: Freeware
Operating System: Linux, Unix, BSD, Win 95/98/NT/2000, Solaris
This library consisting of a single php file implements hierarchical datastructures (trees) using the mysql database.
Developer: Rolf Brugger
License: Freeware
Operating System: any
ADOdb Date and time Library is multi-platform compatible.
Developer: johnlim
License: Freeware
Operating System: Unix/Linux/Windows
This library lets you perform fast and easy-to-program transformations on XML documents.
Developer: Rudd-O
License: Freeware
Operating System: linux, windows, freebsd, osx, sun