Millipede Medicine
Nanoparticles are even smaller crawlers but this creepy robotic millipede can crawl through your blood and across your mucus membranes.
Researchers at City University of Hong Kong have developed a soft robot capable of traversing harsh environment. The prototype is less than 1mm long and could be used to deliver drugs at precise locations within the body.
This Millipede Collection is part of the Soft Robotics that include jellyfish to adhere to the brain and other soft robotic invertebrates created to roam your body.
I have not decided which I detest more, some I can't see crawling through my blood or something larger that I can see crawling through my blood.