A person in jail made a paper knife out of paper and forks. they used 2 forks taped together as the handle and had sevral pices if paper then got less and less paper as it got closer to the sharp end. Then he cut out triangles for a seraded knife.

Well, inmates have been known to make "shanks" out of nearly anything...
Still, even if reinforced, it's unlikely paper would function unless you could stiffen it with some sort of glue or other hardener.