ActiveRecord PostgreSQL Adapter extension for using a cursor to return a large result set
The EmailAddress Gem to work with and validate email addresses.
[For Rails >=3.0 see afair/postgresql_cursor] Ruby on Rails (<= 2.x) plugin to user PostgreSQL cursors.
Resque ported to perl
Ruby gem to interact with the Qmail MTA
Easy Money handling for Ruby instance attributes and methods. Converts between a values stored as integer with an implied precision (cents) and a human-readable/writable money format