darkstat is an ntop-workalike network statistics gatherer. It runs as a background process on a cable or DSL router, uses libpcap to capture network traffic, and has a Web interface that serves up reports of statistics such as data transferred by host, port, and protocol. It also has a neat bandwidth usage graph.
Targa reader/writer is an implementation of Targa reading and writing code that supports 8-bit colormapped, grayscale, 16- and 24-bit truecolor BGR, and 32-bit BGRA, in uncompressed and RLE compressed formats. It honors Targa's "image descriptor" bits, performs appropriate error checking, comes with convenience functions for converting and manipulating the image in memory, and overall has a very simple API.