chrony is a client and server for the Network Time Protocol (NTP). This program keeps your computer's clock accurate. It was specially designed to support systems with intermittent Internet connections, but it also works well in permanently connected environments. It can also use hardware reference clocks, the system real-time clock, or manual input as time references.
jbofihe (or more correctly jbofi'e) is a parser for checking the grammatical correctness of Lojban text. It also provides approximate translations of Lojban into English. (Lojban is a constructed human language with the interesting property that its grammar can be cast into a form that Bison can parse.) The package includes cmafi'e (a smaller version without grammar checking), and a program to aid lujvo (compound word) construction.
mairix is a tool for indexing and searching email messages stored in Maildir, MH, or mbox folders. The index contains a map of which words occur in which parts of which messages. Searches on this index are fast and generate symlinks to the matching messages in a new Maildir or MH folder, or copies of matching messages in an mbox folder, which can be browsed normally in a mail client.
spill manages symbolic links under one tree which point to matching filenames in another. When individual projects are configured with project/version-specific -- prefix= settings, to keep their installations segregated, spill can make them appear to be installed in a common place, e.g. under /usr/local. It can also delete the links associated with a particular program. It is similar in concept to various other programs such as stow, depot, and relink. However, it's written in C, so it isn't reliant on an interpreter being available. It also doesn't assume complete control of the directory tree where the symbolic links are created. It can create both absolute or relative symbolic links, the latter being more convenient in some setups.