For more random interesting theorems with outrageously clever and beautiful proofs, the "Proofs from THE BOOK" [1] book is a fantastic collection. As a curiosity, "THE BOOK" in the title comes from Erdos, who often referred to the book in which God keeps nice proofs of math theorems :)

[1]: https://www.amazon.com/Proofs-BOOK-Martin-Aigner/dp/36420085...