[pdm55]

The story I remember most vividly was the researcher, Dr Karen Wetterhahn, who despite taking great care spilled one or two drops of dimethylmercury on her latex glove. The glove would prove to be no protection at all - tests later showed the dimethylmercury would have seeped through her glove and skin in less than twenty seconds. Karen began displaying the neurological symptons of mercury poisoning some three months later when it was too late to do anything. She was dead within the year.

Dimethylmercury and hydrofluoric acid are both mentioned in this list of "10 Ridiculously Dangerous Chemicals", https://listverse.com/2016/12/09/10-ridiculously-dangerous-c....

[klodolph]

This video covers that story rather well: https://www.youtube.com/watch?v=NJ7M01jV058

[eutectic]

It's kind of scary how easy it is to make too; much easier than e.g. sarin and almost as toxic.