Winnow efficiently trains and operates any number of unique Bayesian (Naive Bayes) classifiers on large sets of content. It has very high performance and works with very small training and unbalanced training sets. It has been used to power an innovative Web feed reader that uses smart tags, which learn and find the content you want to see, from more sources than you can follow with traditional feed readers. It works particularly well with Ruby and Ruby on Rails.
Genit is a framework that builds a static Web site, which does not require a server side programming language or database. Generated sites consist only of XHTML code (plus CSS and media). It runs from the command line, is based on XML, and is designed to be simple, readable, and minimalist.
Tiling provides a simple window tiling system for Linux. It's for those who cannot (or don't want to) use a tiling window manager like awesome or Xmonad. There is no menu or GUI in tiling. You just (optionally) focus a window, press a keyboard shortcut, and that's it -- all windows in the current virtual desktop are tiled.
Ackr is a very small subset of grep/ack/rak, for lazy developers. grep is a great tool, a very powerful tool, but often too powerful for simple needs. Ackr looks for a search string in all text files and in all subfolders from the working directory, is case insensitive, has no options, doesn't look into hidden folders/files, and displays the search term in a bold font.