BlueProximity helps add a little more security to the desktop. It does so by detecting a certain Bluetooth device, most likely a mobile phone, and keeping track of its distance. If it is moved away from the computer and the distance is above a certain level (no measurement in meters is possible) for a given time, it automatically locks the desktop (or starts any other shell command wanted). Once away, the computer awaits its master's return: if the device is nearer than a given level for a set time, the computer unlocks without any interaction (or starts any other shell command wanted).
GroundWork Monitor Community Edition can give you insight into your computing infrastructure, allowing you to see the current and historical states of all your computers: servers, desktops, and laptops, all of your network devices, all of your services (like TCP/IP and Web services), and all of your applications (like mail servers and database apps). You can choose to be alerted when something goes awry via pager, SMS, email, or phone, and even set up automatic restarts or fall-overs.
Logger is a log queueing and optimization utility. It can completely replace sys/klogd, handle logs larger than 2GB, perform automatic nightly log rotation without affecting services, and transfer logs between machines via TCP connections. Any application that writes a text log can be maintained by Logger. It is light, small, and fast, emphasizes security, and reduces drive usage through memory queueing.
Tweeter is another command line script that can update your Twitter status from the command line. It also uses the SSL link to protect your username and password. Tweeter can only post a new status; it cannot follow anyhone, send direct messages, or anything else. The username and password are not stored on the file system, so you can post to different accounts with ease. It should also work on older machines.
Virt-df is a df implementation for virtual guests. The program is meant to be run on the host or dom0 to display disk space used and available on all partitions within all guests. There is no need to run any software or agent inside the guests. It is compatible with most Linux and Windows guests.
Zibu is a small tool that allows you to cyclically compare access permissions and checksums of files provided by users, with a database generated at first run (to be exact, generated with --init or --update mode). But its main feature is restoring valid access permissions, and/or executing your commands when checksums are invalid.