Bitstamp too. Most XRP are traded on Ripple though (it's an exchange after all).
didnt know this, thought bitstamp was only btc
I can't see where you can exchange xrp at bitstamp
You need to exchange your ripple xrp to bitstampt iou btc first in the ripple built in exchange. Then withdraw the btc via bitstamp. Most ripple exchange need ids.