I should have mentioned it, but I think "real-time" would be overkill (i.e. live forex quotes), but generally recent currency exchange rates are easy to get. A

I should have mentioned it, but I think "real-time" would be overkill (i.e. live forex quotes), but generally recent currency exchange rates are easy to get. Also, the variance in shipping costs and sales tax/vat are additional way to help improve comparison accuracy, but getting this right is a whole lot of work, and worse, keeping it up to date is painful. Another consideration would be how various browsers are being faked. If you're spoofing by using a modified user-agent, then the spoof is detectable through javascript. Getting past this could be done either through virtualization or creating a modified client/browser to better emulate the target browser. It's a great project, and I'm looking forward to reading though your code.