US equities, of course, often can have IV over 100%. And it looks like VIX futures options also has a pretty high IV (~80%, calculated from the future). Anything else? I've looked at treasury future options... and if I'm understanding them correctly, the IV is extremely low (in the teens). What about currency, commodity options? Anything else out there an aspiring vol seller might want to look into? Non-US equities? PS. Just for reference, I'm talking about front-month, ATM options.