Monster Sudoku

So, there's now at least one variation of Sudoku - Monster. I found it on the Daily Sudoku. And it comes in 2 sizes - 3x4 (with 12 spaces per box 1-9, ABC) or 4x4 (16 spaces per box, 1-9,0, ABCDEF). Is it possible that some people have too much time on their hands?