CS::SkipList Library is a C++ template library of containers based on skip lists. These containers work like sets and maps, but can also be accessed via numerical index. This collection has vector-like containers where all operations work in logarithmic time. It also has a composite container where you can order the same elements in many different ways at the same time.
TIXI is a fast and simple XML interface library for applications written in C, C++, Fortran, Java, and Python. Although simplified and somewhat restricted compared to a fully-fledged XML processing library, it can create documents, create and delete nodes, and add and remove element attributes. Routines for reading and writing text nodes and nodes holding integer and floating point numbers are included, along with routines that process aggregates of these simple types for the processing of geometric data, multidimensional arrays, or arrays of vectors.
Agnos is a cross-language, cross-platform, lightweight RPC framework with support for passing objects by value or by reference. Agnos is meant to allow programs written in different languages to easily interoperate, by providing the needed bindings (glue-code) and hiding all the details from the programmer. The project essentially serves the same purpose as existing technologies like SOAP, WSDL, CORBA, and others, but takes a minimalistic approach to the issue at hand. Unlike the aforementioned technologies, which tend to require integration with Web servers, using verbose XML-based protocols on top of textual transports (HTTP), often also requiring complex topologies (such as name servers for registering objects, etc.). Agnos is designed to be simple, efficient, and straightforward, allowing for direct communication between two ends using a compact binary protocol.
uma::bson is a DOM-style C++ API for reading/writing BSON data. Unlike the MongoDB C++ API, which exposes a read-only interface with a separate interface for creating a BSON representation, this API allows reading/writing on the existing data. The API is designed primarily for serialising/deserialising BSON data to/from streams (files, socket connections, etc.).