glbmp is a lightweight and portable partial glaux replacement, providing auxDIBImageLoad and related device-independent bitmap image loading functionality. At the basic level, it's a flexible bitmap loader and decoder that can be used anywhere the color data of a bitmap is required. It supports uncompressed monochrome, 16 color, 256 color, and 24-bit bitmap files of any size, and allows for flexible output formats.
Adime is a library for constructing Allegro GUI dialogs in a way similar to scanf(), using a format string. Other features include a (customizable) 3d look and feel, 3d versions of some of Allegro's GUI procs, complete help in many formats (HTML, txt, chm, texinfo, man, devhelp, and RTF), and four example programs. Adime can currently be compiled on Linux, Windows/MinGW32, Windows/Borland C++, Windows/MSVC, DOS/DJGPP, DOS/Watcom, Apple MacOS X, and QNX.
HappyHTTP is a simple C++ library for issuing HTTP requests and processing responses. It is simple to integrate: just drop in the .h and .cpp files. It has an easy-to-use interface, non-blocking operation (suitable for use in game update loops), and pipelining support (you can issue multiple requests without waiting for responses).