Currency conversions in Google Spreadsheet

Just learned a tip in Google Spreadsheet.

To get the currency conversion rate between TWD-USD:

=GoogleFinance("CURRENCY:TWDUSD")

That will give you the rate from Google Finance database, history is also available.

=GoogleFinance("currency:USDTWD", "price", today()-10, today())

Other API parameters:
https://support.google.com/docs/answer/3093281

Reference:
http://googledocstips.com/2011/03/09/how-to-calculate-foreign-exchange/
http://stackoverflow.com/questions/20607627/on-google-spreadsheet-how-can-you-query-googlefinance-for-a-past-exchange-rate