Hahaha... I should really be shouting this out...
If you are doing big numbers... sign up for Paypal in the UK. 1.4% for UK transactions and 1.9% for other currencies/countries. You need to be doing a considerable amount per month but you are basically getting wholesale rates with Paypal processing for nothing extra. Google matches the lowest rate but foreign transactions are 2.4%.
Just be careful for Paypal's conversion fees. They are 2.5%. You can avoid them by adding foreign bank accounts.
Dealing with Paypal is not for everyone. That is why I don't use them anymore. Got a more suitable service with another provider but it is not a service that most people would be able to use.