Is there a book called "mathematical pranks"? A friend told me that there is a book named something like "Mathematical pranks" which lists tricks to mathematically fool and prank your friends like fake and false proofs that look ok and so. But I can't find the book. Do you have an idea what I'm talking about?
 A: Although there probably is no book with that title, Linderholm's Mathematics made difficult is exactly that: a collection of pranks.
As the title says, it consists of absurdly sophisticated proofs of  trivial or easy  results.
For example here is the Wikipedia page reproducing the proof that $2$ is a prime number.   
There also are interesting asides:
On pages 37-38 you will read "    It is not correct in logic to prove something by saying it over again; that only works in politics, and even there it is usually considered desirable to repeat the proposition hundreds of times before considering it as definitely established              "
On page 156 called A parenthesis on the sex life of brackets you will learn about "the special liaisons which occur chiefly in  France: monstrosities like  $[a,b[$ in which two brackets of the same sex join horribly".
Anyone aware of the recent  law in France authorizing same-sex marriage (just Google "Le mariage pour tous") can only stand in awe before the eerie prescience displayed by the author. 
The book is out of print, but it is very easy to find links on the Internet for downloading a PDF version of it.
