Magento - Link to Store With Specified Currency

The default currency on my store (http://twistedtime.com) is GBP. Is it possible to create a link which would open the st开发者_高级运维ore with a specified currency ie. USD.

When advertising on US based sites I'd like the store to open with USD as default.

You could write a plugin and detect locale to select a default currency then save it with sessions.

en-GB => GPB
en-US => USD
fr-FR => EUR

etc...

Mage_Core_Model_Store has a setCurrencyCode() method.