They can't unsee this...
Danger Zone

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I used to do tech support in a major research institution, and some of the computers we worked on were in darkrooms which were used to develop gels–they are these little jelly-like plates with stripes on them that are used in biology to examine DNA. They are developed sort of like camera film with a chemical called ethidium bromide. Ethidium bromide is a potent mutagen, causes cancer and birth defects. Especially if it is inhaled as a powder.
Over time the computer fans would draw in ethidium bromide vapor and the inside of the computers become coated with a sort of white crust. We used to open the cases and blow this crusty dust out with compressed air. Nobody told us it was dangerous as hell.
When we found out we were pretty outraged, went to the company safety officer, went to management, all that. They were completely unconcerned and their solution was to give us a box of latex gloves and tell us it was our job to check with the lab manager if we thought anything might be dangerous in a lab. (FoodTruckNation)
Fried Bugs

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For consoles, cockroaches. None alive thankfully but man, just systems full of hundreds of cockroaches, some of them fried on the board. The smell is even worse. We don’t work on those, even when it’s working. For health and safety reasons, we bag those and throw it out. (tocilog)
Just the Shoes

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I fixed my dad’s computer and found a 1.8gb folder of high heels and other shoes. Mostly just the shoes. Not anyone wearing them. The folder was labeled “dream big” (ThoseArePenguins)
Maybe he has a secret dream of becoming one of the world’s best shoe designers? (dzzi)