Steve Hanke has charted the collapse of the Iranian rial:
I have conflicted feelings about this:
1) Sadness: this must be causing great hardship for the Iranian people
2) Comfort: this must be weakening the regime, particularly their ability to buy foreign weapons.
3) Discomfort: this collapse (following an embargo) was orchestrated by a regime with a history of dominating and exploiting foreign countries. In some sense, this is just another battle in the wars among various ruling classes.
4) Satisfaction: while any community would suffer from economic isolation, I think that the Iranian state has largely brought this on themselves, and this type of collapse is essentially inevitable. Better to get it done sooner than later (assuming that the regime is replaced with a more humane one). The Iranian state has suppressed the creativity and initiative of the Iranian people, and their economy consequently is weak. This "black-market" deviation from state-sanctioned exchange rates indicates that the Iranian state is being sidelined within the Iranian economy. Every black-market exchange is a tiny revolution (a la Agorism).
tip Marginal Revolution