Poedit is a gettext translation (.po file) editor for Unix, Windows, and OS X. It aims to provide translators with a simple, easy to use user interface with all the essential tools such as spellchecker or translation memory. It can also be used to manage translations for small projects.
The libmba package is a collection of mostly independent C modules potentially useful to any project. There are the usual ADTs including a linkedlist, hashmap, pool, stack, and varray, a flexible memory allocator, CSV parser, path canonicalization routine, I18N text abstraction, configuration file module, portable semaphores, condition variables, and more. The code is designed so that individual modules can be integrated into existing codebases rather than requiring the user to commit to the entire library. The code has no typedefs, few comments, and extensive man pages and HTML documentation.
libmime is a MIME parser in the same vein as Expat, the stream-oriented XML parser. As input is fed to the parser, events are generated which an application can catch by registering event handlers. Such events include the Unix From_ line, start of entity, end of entity, entity boundary, header, end of headers, and body. libmime supports MIME message editing through a delta mechanism. Edit contexts are instantiated and changes applied to specific contexts. Edit contexts can then be expressed in standard unified diff format which, when applied to the input source stream, will result in the new message.
Flexible Localization is a .NET/Mono library for string-based user interface localization. It offers a hierarchical structure (which can be partially loaded) to organize the strings, as well as support for several independently-localized modules. Localization files are validated against a localization declaration which defines the actual strings that are expected to be in the localization files. The strings themselves can be parametrized and evaluated based on expressions (i.e., different strings can be returned by a localization, based on parameter values).