PHP Shell is a shell wrapped in a PHP script. It's a tool you can use to execute arbiritary shell-commands or browse the filesystem on your remote Web server. This replaces, to a degree, a normal telnet-connection. You can use it for administration and maintenance of your Web site using commands like ps, free, du, df, and more.
Finnix is a small, self-contained, bootable Linux CD distribution ("LiveCD") for system administrators, based on Debian testing. You can use it to mount and manipulate hard drives and partitions, monitor networks, rebuild boot records, install other operating systems, and much more.
The GNOME NetworkManager is a set of co-operative tools that make networking simple and straightforward. Whether wireless or wired, NetworkManager allows you to quickly move from one network to another: once a network has been configured and joined once, it can be detected and re-joined automatically at a later date. It was designed to auto-detect as much information as possible, seamlessly switches connections when necessary, and provides immediate feedback of the network state to users and applications.
BitNami RubyStack provides a fast, easy way to develop and deploy Ruby on Rails applications. It includes Ruby, Subversion, MySQL, SQLite, ImageMagick, and several Ruby Gems, and will optionally install Apache 2.2 with rewrite and proxy support. It supports Windows, Linux, and OS X, so you can share the same Rails environment on multiple platforms.
UDPCast allows to send data simultaneously to many destinations on a local net. This can for instance be used to install entire classrooms of PCs at once. The advantage over using other methods (nfs, ftp, whatever) is that udpcast uses Ethernet's multicast abilities: it won't take longer to install 15 machines than it would to install 2. The tool comes with a busybox bootdisk for easy loading of the tool. However, udpcast can also be started from the command line of an already installed system, and can be used for other purposes than just system installation.
mrepo (formerly known as Yam) builds a local APT/Yum RPM repository from local ISO files, downloaded updates, and extra packages from RHN (Red Hat Network) and 3rd party repositories. It takes care of setting up the ISO files, downloading the RPMs, configuring HTTP access, and providing PXE/TFTP resources for remote installations. It was primarily intended for doing remote network installations of various distributions from a laptop without the need for CD media or floppies, but is equally suitable for an organization's centralized update server.
TurnKey Ruby on Rails Appliance is a server appliance for the Ruby on Rails Web development framework. It is designed to be easy to use and easy to maintain. Security patches are automatically installed. It provides a Web management interface, configuration console, and an AJAX Web shell. To minimize footprint the appliance is built from the ground up with the minimum required components. It runs everywhere thanks to multiple build formats, including an installable live CD, a VMDK with OVF support, and an Amazon EC2 AMI.