Uunique_ids is a project mainly written in Ruby, it's free.
uunique_ids - Lightweight wrapper for standard UUID tools
uunique_ids was developed by: tracy
gem 'uunique_ids','0.1' require 'uunique_ids'
UUniqueIds.random_create => (SHA1) 6d480cd113b430b91c9a537b66067edb184a184e