Command line tool for converting between currencies using data from openexchangerates.org.
Requires a free
openexchangerates.org API key
to be set as the environment variable OER_APP_ID:
$ export OER_APP_ID=yourapikeyhere
$ forex.py 1 GBP USD
1.676 USD
Also does historical end-of-day rate conversions from 1999 onwards:
$ forex.py 37 GBP USD -d 1999-03-27
60.090 USD