Microchips are not GPS devices. I get some clients that ask this too so might as well just get is cleared up. Also, microchip needles are huge. Flu shot needles are not. You cannot tell someone they are getting a flu shot and sneak in a microchip.
There is no vet school in Bloomington, Indiana.
This next one is not even fiction. Just a case of poor research and planning that we saw on 48 Hours. Two teenagers tried to commit suicide by putting rat poison on their cereal. There are several problems with this. You need to eat A LOT of rat poison to kill a person. They did not eat enough. Also this is not a quick and painless death. You don't just fall asleep and not wake up. You will more likely bleed to death internally over several days. If you are really lucky you could bleed into your brain and die quicker. And to top it all off you won't even start bleeding for a few days-you need to wait until all your clotting factors are used up.
Another real life medical murder disaster (as seen on Dateline or other such show)-killing someone with the animal tranquilizer xylazine. Yes, in theory it can be done. But this also takes a large amount and is really not practical. There are better ways. The best being of course, not at all.