Iranian Currency Drops 60% in 8 Days. Police Battling Demonstrators

I'm hoping that President Obama doesn't repeat the "Hungary '56"** approach, encourage the demonstrators, even tangentially, and then leave 'em to suffer the tender mercies of the successors to the SAVAK.
He came close to doing it during the "Green Revolution" of 2009.
From FT Alphaville:

Gresham’s law takes Iran

What’s happening in the Iranian currency markets at the moment is getting pretty fascinating.
Via Reuters on Wednesday:

IRANIAN RIOT POLICE CLASH WITH DEMONSTRATORS IN TEHRAN OVER RIAL COLLAPSE – WITNESSES

So, the back story is that sanctions have for a long while been causing a huge squeeze on the black market’s currency of choice — the dollar. Supply of which Iran obviously cannot freely regulate.

As a consequence, it’s become ever harder for the central bank to pass off any semblance of an official rate. And Iran has been put at the mercy of oil-related dollar inflows.
It’s important to note, of course, that the reason the depreciation and associated inflation has been so intensive is almost entirely connected to the scarcity of goods associated with sanctions.

As Bank of New York Mellon’s Neil Mellor noted on Wednesday:

Indeed, the collapse in the Iranian Rial is indicative of the intensifying impact of global sanctions on the country and the accompanying pressure on its government: President Ahmadinejad yesterday denounced the West’s economic “war” whilst industry minister Ghazanfari today promised to “root out” speculators.

But here’s where it gets interesting....MORE

**Although there is disagreement as to the official U.S. response to the events in Hungary, a post-revolution review of Radio Free Europe broadcasts found transmissions such as:

if “the Hungarians hold-out for three or four days, then the pressure upon the government of the United States to send military help to the Freedom Fighters will become irresistible!” and

“Western reports show that the world’s reaction to Hungarian events surpasses every imagination. In the Western capitals a practical manifestation of Western sympathy is expected at any hour.”

RFE didn't instigate the Revolution although their coverage of the Poznań riots earlier that year probably contributed some inspiration.
Here is the Hoover Institution archive.
Here's the Wilson Center ""Setting the record straight..."