A post as a note to myself to remember some Ruby Idioms ..
# $ruby 1.9.2
#
# Add a value to an array unless its not 
# contained already and even it's contained 
# multiple times reduce it to a single occurence.
foo  = ['bar', 'baz', 'baz']    # =>  ["bar", "baz", "baz"]
foo |= ['baz']                  # =>  ["bar", "baz"]
# Parallel assignment by "un-splatting" an result array
# Instead of:
match = "Ruby 1.9.2 is awesome".match(/Ruby (d.+) is awesome/)
catch = match[1]
# Use:
catch, match = *"Ruby 1.9.2 is awesome".match(/Ruby (d.+) is awesome/)
# catch => "Ruby 1.9.2 is awesome"
# match => "1.9.2" 
more to come..