Cashish is a project mainly written in Ruby, based on the MIT license.
Simple Currency handling in Ruby
Storing Currency as Integers Cashish (will) make it easy to display this with the right number of decimal places. As well as creating a simple "Amount" object you can perform arithmetic on.
gbp = Cashish::Amount.new(1_000_000_00, "GBP")
gbp.to_s
=> "1,000,000.00 GBP"
gbp.to_f
=> 1_000_000.00
gbp.to_s(:simple)
=> "1000000.00"