Over the years, the international settlement rate between telcos has come under pressure as the cost of making IDD calls continues to fall, but there's still good money to be made.
Tip : some termination points like Diego Garcia offer good rates on paper, the connectivity/access can be poor. So for a global access number, sometimes better to take a lesser rate with good connectivity.
www.phonecash.tv will soon be expanded to include IPRS services such as Arabic stories.
In the meantime, you could always approach a company like
www.mediatel.com just for numbers.
As for applications, check out
www.chatterwith.me - this allows anyone to set up ad hoc phonesex services, with domestic and international numbers included, and up to 600 participants at a time.
