The Jawzall is an incredibly freaky chainsaw-blade that is sheathed in shark teeth. Don't worry, this unforgiving creation won't be available in hardware stores near you or near anyone you care about -- it was created by researchers at Cornell University who wanted to compare the cutting power of different kinds of shark teeth. And so they did what any reasonable person would do -- built a saw blade covered in shark's teeth, hooked it up to a Sawzall and annihilated a hunk of salmon.
The Jawzall blade used the teeth from sixgill, sandbar, silky and tiger sharks. The cutting-edge demonstration found that larger teeth with more serrations were more effective at cutting through flesh and bone. However all the teeth showed signs of wear and tear after about twelve cuts, which explains why sharks shed and re-grow teeth so frequently.