RFind indexes the filenames of a given directory, and allows you to quickly search this index with regular expressions. Search-on-typing with more than 500,000 indexed filenames is easily possible. This tool attempts to be very configurable so that it can be useful to everyone. It features hierarchically presented search results, search-on-typing, and the ability to define rules to execute on mouse click.
Tmpf is tiny script (written in Ruby) to write standard output to a temporary file, run an application with the name of that file as an argument, then delete the temporary file when done. This is useful when you want to pipe output to a program that only accepts files, not standard input. Example: cat myfile.ps | tmpf gv (equivalent to: gv myfile.ps). Despite the incredible simplicity of this script, there is nothing quite like it provided among the standard Unix tools.
The Ruby Crypt library is a Ruby implementation of a number of popular encryption algorithms. Block cyphers currently available include Blowfish, GOST, IDEA, and Rijndael (AES). Cypher Block Chaining (CBC) has been implemented. Twofish, Serpent, and CAST256 are planned for release soon. It is written entirely in Ruby so deployment is simple: no platform concerns, no library dependencies, and nothing to compile.
AffirmIt! is a supportive testing framework for Ruby. It tolerates all code, whether it exhibits behavioral challenges or not. It never uses the words "test" or "failure", which would imply a value judgment, or "assertions," which would imply an absolute truth. Instead, it treads softly around code and espouses preferences.