Yeh in European countries you can drive with a full licence, but further afield i think i remember reading you need to order a permit, not sure if thats the same as a IDP?
When i went to Turkey last year, i hired a scooter, which was loads of fun and really cheap, something like 10 million for a whole day. I think you may have needed a licence or something, but they just werent bothered, i didnt even wear a helmet and passed loads of police, here my friend did that on his scooter and got prosecuted, £100 fine and 3 points!