Experiance-based Ruby book for hackers. This gem, allows you to browse the book offline
Rubyful Soup is a *ML parser that makes screen-scraping easy. It won't choke on bad markup, and it's easy to locate the part of a document you want.
漢字かな交じり文に、ひらがなとローマ字のふりがな（ルビ）を付けます。
Brainfuck compiler written in Ruby - highly serious project
A Befunge-93 interpreter written in ruby.
Finally updated this to work 1.9.2 so we can use it with our flybymiles app