Sorry.. I'm not sure what you mean by 'exchange risk'.

To your question though.. no I cant bill directly in USD. I am very new (and ignorant) to receiving online payments, so I'm really curious what the issues for Americans are. The on-line currency converters are accurate to (I would guess) +- 1hour currency fluctuations so would give a very accurate estimate (to within cents) of the cost of a transaction... Wouldn't this be good enough?

Otherwise if this is an issue then paypal should do the job... 2 mins to set up and gives an alternative option.

Would be good to hear your own personal experiences.