gistfile1.txt

class User < ActiveRecord::Base

  def display_name
    full_name || email_designator || "I haz no name nor email!"
  end
  
  def email_designator
    return nil if email.blank?
    @email_designator = email.split("@")[0]
  end

  def full_name
    @full_name = "#{first_name} #{last_name}"
    @full_name unless @full_name.blank?
  end
  
end

Much nicer solution.

Perfect!