JAM Message Base Library
JAM is a popular messagebase format for storing Fidonet messages originally devised by Joaquim Homrighausen, Andrew Milner, Mats Birch and Mats Wallin. JAMLIB is a subroutine library for manipulating such messagebases.
Flexible Properties (FProp) - library to manipulate by property trees in Qt projects
.NET(including CF), Mono, and FreePascal(planned) ports of one library aimed to simplify working with database data, and some other routines.
jFuzzyDate is a lightweight java library for formatting easily readable time distances, durations and dates.
xmlbipargen is a program for generating binding XML parsers for C programs, using description in XSD file