Ten Mint-Condition Issues of Fantastic Four
Around 1967, my step-father refused to underwrite my investing in ten mint-condition issues of Fantastic Four #1 (at IIRC $20 each from the Howard "Ripoffsky" ad in the comics). I had this crazy idea they'd become more valuable.
Before he died, I did get to tell him about a copy of FF#1 selling for something over $100,000.
Near-Mint, if you can find one: $142,000.
If he were still alive, and I hadn't had my comics collection stolen in 1978 anyway, I figure a lawsuit for $2,000,000 would be about right.