Hexoku.org

Something different, but looks similar. If you have tried Sudoku, here is something that looks similar - called Hexoku.org

Hexoku uses the hexadecimal (hex) numeral system (with a base of 16).
It uses sixteen distinct symbols: 0-9 to represent values zero to nine and
A, B, C, D, E, F to represent values ten to fifteen.
The rules are simple:
- enter digits from 0 to 9 and letters from A to F into the blank spaces.
- every row, column and 4x4 square must contain one of each symbol.
- you can change the puzzle difficulty by selecting easy, medium or hard