You can trade volatility of volatility (e.g. VIX options), or even volatility-of-volatility-of-volatility -- except the greater the degree of derivative, the fe

You can trade volatility of volatility (e.g. VIX options), or even volatility-of-volatility-of-volatility -- except the greater the degree of derivative, the fewer options you have to trade using publicly-listed securities. Also, even if there are publicly-listed securities, the lesser the liquidity and thus the harder/impossible to get in-out of trades. This can work if you are a big firm with access to private contractual derivatives, but you would still suffer from the 2nd problem: liquidity.