Consume currency exchange rate web service

Create a customization which consumes a free web service that provides currency exchange rates.


http://msdn.microsoft.com/en-us/library/hh500187.aspx
http://axwonders.blogspot.com/2011/04/consume-currency-exchange-rates-web.html
http://dynamicsuser.net/blogs/dynamicsnavax/archive/2011/06/19/update-exchange-rate-using-yahoo-web-service.aspx