Support multiple currencies

Yes, I did try that, but none of the modules I found seemed to do what I wanted...

CCK Currency: Provides a drop-down list of currencies, but from what I understand, doesn't do anything past that (like change existing prices based on selected currency)
Money CCK field: Provides a field to enter an amount into and select the currency, but I'm looking to automatically convert the price, not have to enter multiple prices when creating a node...
Currency Exchange: Simply provides an exchange where users can get different currencies for amounts they enter, not automatic.

I don't know enough about module development to combine these to get the functionality I want - I was hoping there was a module (like the locale/content translation module(s)) that automatically converted prices to one of the enabled currencies...