We have $500 in OBC. We have already paid for the drink package and excursions. On Royal, you can use your OBC for pre-cruise purchases, but I don't remember that offer being made when I purchased the drink package and excursions on the Carnival site.. I'd like to pre-pay internet for the 15% discount, but I'd really like to use some of that OBC. I tried putting it in my cart and I still don't see any way to use OBC to pay for it. Am I missing something, or does Carnival not allow the use of OBC for pre-cruise purchases? Also, can you use OBC for getting cash in the casino? Even if I use the $500 for grats and internet, I still won't use it up.