Displaying Cart Total in Alternate Currency?

[8900200]

I need to show this on the check out page. We have all our prices in Euros, but we need to display the price equivalent in US$ when the total amount is calculated in case the user is from the USA. I don't see a tag for this. I sure hope there is some way to do this. I'm notesure how useful the Alternate currency is if all it does is display next to a product and you can't use it anywhere else in the system.

Thanks
Rich