linkchk is a network link ping monitor. It supports both IPv4 and IPv6. It works by repeatedly pinging a named host or the default gateway of a given interface. When the link is working the ping time is shown in a small GTK window or tty, otherwise the link status is shown. It is particularly useful for monitoring IP tunnels or dialup links.
Debian From Scratch is really two related components in one. First, it's a live bootable CD image that is designed to provide a full-featured kernel and rescue environment. It includes filesystem tools, editors, C compilers, Python, Perl, and everything you need to manually install Debian on a new machine. On ix86 machines, Grub is used to boot directly from the CD. There is also a program that is used to create the DFS CD images. It is highly configurable and can be used to create other custom bootable CD or DVD images. You can include whatever kernel or packages you want.
Streams is an I/O library designed to eventually replace the current I/O facilities based on using Handles. The main advantage is its strong modular design using typeclasses. It consists of small independent modules, each implementing one type of stream (file, memory buffer, pipe, etc.) or one part of common stream functionality (buffering, char encoding, locking, etc.). 3rd-party librarie can easily add new stream types and new common functionality. Other benefits of the new library include support for streams functioning in any monad, Hugs and GHC compatibility, high speed, and an easy migration path from the existing I/O library. It is heavily based on the HVIO module written by John Goerzen.