# takes a number and options hash and outputs a string in any currency format
def currencify(number, options={})
  # :currency_before => false puts the currency symbol after the number
  # default format: $12,345,678.90
  options = {:currency_symbol => "$", :delimiter => ",", :decimal_symbol => ".", :currency_before => true}.merge(options)
  
  # split integer and fractional parts 
  int, frac = ("%.2f" % number).split('.')
  # insert the delimiters
  int.gsub!(/(\d)(?=(\d\d\d)+(?!\d))/, "\\1#{options[:delimiter]}")
  
  if options[:currency_before]
    options[:currency_symbol] + int + options[:decimal_symbol] + frac
  else
    int + options[:decimal_symbol] + frac + options[:currency_symbol]
  end
end