In 1898, Bier was responsible for the first successful attempt at spinal anesthesia, proving to the medical community that regional numbing was possible. This opened the door for countless advancements in surgery and medicine, and it was all thanks to one man who dared to ask the question, "What's the worst that could happen if I shot cocaine into my spine?"
Unlike the other entries on this list, Bier first experimented with his new anesthetizing technique on a surgery patient instead of himself. The man was suffering from adverse reactions to the general anesthesia, so Bier gave him what may have been the coolest experimental option in the history of medicine, offering to just inject 15 milligrams of coke directly into the man's spinal cord.
It worked, too. The patient felt no pain during or after the surgery, which encouraged Bier to do further testing using intrathecal injections. With the help of his colleague, Dr. Hildebrandt (who was weirdly also named August), Bier tried to inject himself to really understand the effects of the drug.
Kids, you can use that excuse the next time you get caught trying to "understand" a controlled substance.