Shell In A Box is a web based terminal emulator.
Originally written for Wikipedia. It is now used by several other projects of the non-profit Wikimedia Foundation and by many other wikis.
Greyhole is an application that uses Samba to create a storage pool of all your available hard drives.
Amahi Netboot allows you to boot a computer on your local network off of an image stored on your HDA.
Sonarr is a PVR for Usenet and BitTorrent users. It can monitor multiple RSS feeds for new episodes of your favorite shows and will grab, sort and rename them.