Tactor is a tool that tries to guess the best action for the current text selection. For example, text containing http://xyz.com is recognized as an URL link, and ~/Documents/MyPresentation.key as a presentation file. Both matchers and actions are fully customizable. It is loosely based on Plan9’s Plumber where any text can potentially be an action, although the actual technical implementation is very different. It provides functionality somewhat similar to that of Apple Data Detectors in a way that is fully extensible and transparent.
ActoTracker is an application for keeping track of activities on your desktop so that you don't have to. Think of it as an app for bookmarking desktop documents and applications. It can also bookmark things that are not usually tied to a URL such as Outlook email message or Filemaker records. It can be extended to handle additional applications by writing custom AppleScript plugins. ActoTracker is somewhat inspired by the GNOME Activity Journal (Zeitgeist framework), and it tries to solve a similar kind of problem for the end user, although in a different way.
PixSteward downloads pictures and metadata from your Flickr accounts and archives them in a relational database on your computer, allowing offline searches and image exporting. With PixSteward, you can safely back up multiple Flickr photostreams with metadata to your Mac, perform sophisticated searches (even where there's no Internet connection), rapidly browse your picture archive and export original-sized JPEGs, PNGs, and GIFs (groups and one-by-one), export sets of pictures along with their metadata for use in other apps, and edit your Flickr tags, titles, and descriptions simultaneously on Flickr and within PixSteward.
DNSCrypt OSX Client is a user interface to conveniently start/stop dnscrypt-proxy and change DNS settings. It was specifically designed to use DNSCrypt with the OpenDNS public DNS resolvers. It includes a preference pane, a menu bar indicator, and a set of scripts for interacting with the system.
LibRCrypt is an Objective C library for complex data encryption based on Rubik's Cubes. The idea's pretty simple: If you represent data as the squares on a Rubik's Cube, you can apply transformations to the data and get back encrypted data, all of which is commutatitive. Just as a Rubik's Cube can be solved if you know all of the moves, this data can be "unwound", so to speak, if you know all of the transforms applied, but the encryption is even deeper than that. A cube can only cover (9 squares per face x 6 faces) 54 significant bits of data. Therefore, compressed data must be composed of multiple (even thousands) of Rubik's Cubes.
Mr.Java is a Java IDE that is one step above a command line interface, but not quite as confusing as an IDE. It will compile for you, add libraries to your class path, and run the whole thing, with three simple buttons. Drag a library or Java source file over the window, and it will be put in the right folder. When running programs, the stout is written to a file cleverly named “stdout”, and the std err is cleverly written to file named - you guessed - stderr.