Most frequent letters, in order, occurring in the 1000 most common words (http://www.giwersworld.org/computers/linux/common-words.phtml)

Character_Frequency.rb

# This is a dump of the word list
text = File.read ARGV[0]
words = text.split("\n")
hash = {}

words.each do |word|
  word.each_char do |l|
    hash[l] ||= 0
    if hash.keys.include?(l)
      hash[l] += 1
    end
  end
end

p hash.sort_by {|k, v| v}.reverse