GeoQO is a waypoint, geocaching, and waymarking database. It is extremely fast and offers a wide variety of utilities for manipulating waypoints. Though designed for geocaching and waymarking, it should be usable for any waypoint management. It is highly extensible; writing new import, export, search, display, and other plugins is easy to do.
The Net-Policy project allows system administrators to configure and manage their entire network at once. It is initially designed to configure firewall and IPsec connections across an entire network, but will eventually include the ability to control and configure just about anything. It uses a role and policy based data-model concept so reconfiguring a device usually just means assigning or removing a role to/from it. Initially the software comes with a completely configurable IPsec and IKE software suite for Linux. Stop configuring your network one device at a time!
The NET-SNMP (formerly UCD-SNMP) package contains various tools relating to the Simple Network Management Protocol including an extensible agent, an SNMP library, tools to request or set information from SNMP agents, tools to generate and handle SNMP traps, a version of the unix 'netstat' command using SNMP and a Tk/perl mib browser. It was originally based on the Carnegie Mellon University SNMP implementation (version 220.127.116.11), but has been greatly enhanced, ported and fixed and barely resembles the original package anymore.
qmailcheck looks for new mail in multiple IMAP mail boxes. If you get a lot of mail and split the messages into separate boxes (typically on the server side using procmail or sieve), then checking all the boxes by hand can be tedious. QMailcheck displays the results in a formatted list, highlighting the newest items. When new mail arrives in a folder, it is capable of raising the window, issuing a system notification, flashing the LED (on phones only), and vibrating (on phones only), all on a per-folder basis.
If you're a developer of multiple projects, you'll find yourself needing to switch between multiple different version control systems. After working in one (e.g. SVN) for an hour, you may need to switch to a different one (e.g. git). Getting your fingers to switch is the difficult part, or remembering the right command line flags to use for the given tool. That's where The One Ring comes in: it provides a constant interface to all the version control systems, and your fingers only need to remember a single command regardless of what checkout directory your shell is sitting in.