simsicon's Stars
minimagick/minimagick
mini replacement for RMagick
collectiveidea/awesome_nested_set
An awesome replacement for acts_as_nested_set and better_nested_set.
rsl/stringex
Some [hopefully] useful extensions to Ruby’s String class. It is made up of three libraries: ActsAsUrl [permalink solution with better character translation], Unidecoder [Unicode to Ascii transliteration], and StringExtensions [miscellaneous helper methods for the String class].
mojombo/chronic
Chronic is a pure Ruby natural language date parser.