A friend of mine just showed me this today and it might be common knowledge, but I figured some of you may not know this already -
Paypal by default converts foreign currency themselves and uses a currency rate that benefits Paypal, not the consumer. Some of us are getting screwed on currency exchange when buying from foreign retailers
You can tell Paypal to bill you in the currency of the retailer. Go to Profile > Payments > My Preapproved Payments > Set Available Funding Sources > Conversion Options
Now you might end up getting screwed by your bank or credit card company on the exchange rate in addition to possible fees that would accompany the transaction, but that would depend on the financial institution you deal with. In my case, my bank's exchange rate is significantly better than paypal.