So I've just enabled another currency. For one event, two forms are available to sign up in either US$ or in CAD$.
In the reports, how will CiviCRM show the revenue totals ? Does it know the exchange rate from US$ to CAD$ ?
If you install Fuzion's Extension: ExtendedReport (nz.co.fuzion.extendedreport) - specifically the Line Item report for price sets - then you can pull currency into your Reports; here's a screenshot of what that looks like (for a variety of Donations/Events pages).
You can then make a report a) for one currency and b) for another currency [using filters]. Hope that helps!
I am afraid that CiviCRM will not provide a lot of features out of the box for multi-currency use. Also, it does not know exchange rates (in fact it only stores the currency and one amount value - not both).
Searches and reports will usually not differentiate between the currencies and (depending on your requirements) you may have to invest quite some time to improve reports & usability.
We thought about doing a exchange rate extension at some point but it is not quite that easy (particularly as they are fluctuating, and may be different when a contribution is created, completed...).
However, apart from the lack of features in the UI, the "currency-information" is stored properly in the database and will allow you to base custom reports & functions on it e.g. using custom reports & searches, drupal views, Civisualize or custom reporting tools such as pentaho.