The Following is taken from
another guy's post, but I'd like to do the same thing, so here it is:
So, you got your free Ripples in a Giveaway (
https://bitcointalk.org/index.php?topic=145506.0), but have no use for them? Sell them to me, here is the procedure:
1) Check current buy rate (see the next post).
2) Login to your Ripple client.
3) Click "Send" tab, transfer your XRP to my address rsjza6RzdeU2GSCqHLvVoZXcfr7HnqrXu1, confirm.
4) PM me on Bitcointalk with your Ripple address (to check the amount of XRP that you sent) and your bitcoin address.
5) I will send the appropriate amount of BTC to your bitcoin address as soon as I confirm your transfer. This will take no longer than 24 hours, usually under 2 hours during daytime PST.
I only need a limited quantity of Ripple XRP for my experiments. So I reserve the right to stop buying XRP once I get enough. Any transfers I get in excess of my needs I'll return to the sender at once.