Juan Cole has reported on a just released recording that may be by recently wounded Ibrahim al-Samarra'i, more widely known as Abu-Bakr al-Baghdadi, although apparently reverting to "Irahim" since he declared himself Caliph (Khalifa) of the Islamic State (Ibrahim is the Arabic version of Abraham). He calls for terror attacks to be made on Saudi Arabia, for Shi'a to be specifically attacked both in Saudi Arabia and also in Yemen where the Houthi Zaydi Shi'a have seized control of Sana'a, the capital of Yemen, and also their plans to "mint money" to save the Islamic state from the "infidel finance" imposed on "Muslims by the West." It has not been verified that the recording is by him, but at least probably reflects his thinking, and also does seem to be his response to being wounded in the US attack near Mosul, which Daesh now recognizes happened.
One remark on this is that Saudi Arabia is arguably the fountainhead of the particular brand of Islam that al-Samarra'i espouses, Wah'habism. I have posted here previously on the close relationship between it and Salafism, which is regularly muddled in most ignorant western commentary. They overlap, but have some differences and origins, and while Daesh is clearly influenced by both, it looks like the Saudi Wah'habism is more important. So, Saudi Arabia's alliance with the US makes them the "head of the snake" according to this message that must be "cut off."
On the matter of minting money, there are two aspects of this. Of course, strict Islamists support interest-free banking, so-called Islamic banking,which in fact exists in many countries, including the US. It is well established, although only a handful of countries impose it as the only allowed form.
The other aspect is probably bullionism, which is found in the Qur'an. Money should only be gold and silver. Indeed, the very strict Saudis have silver threads in their paper money to obey this, and the late Nelson Bunker Hunt got current Saudi King Abdullah to lose a few billion in the great silver bubble and crash of the early 80s on a claim that the world was going to go on a silver standard. I do not know what form this Islamic State money will take, but I suspect they may imitate what the Saudis do and adhere to bullionism.