In case you ever feel bad about selling early…
In 2012 I spent 30BTC on Silk Road (after tumbling my coins three times but I have a feeling that whole process was unnecessary) for a single sheet of acid. They were Jerry Bears from a vendor in the Pacific Northwest that went by HouseOfSpirits. I spent that money joyfully and gratefully because, for the time time in over a decade, I could find really good acid.
Today that would be worth $1,500,000
Or $15K per hit. I have around five of them left. I think that qualifies as the most expensive acid in the world.