We have covered various Speed Cube Puzzles here in the past. If you thought solving this 13x13x13 Cube Puzzle was hard, wait till see the guy in the below video solve a 17 x 17 x 17 puzzle. The whole video is just over 6 minutes, but the process took over 7.5 hours! Kenneth solved the puzzle using the reduction method. As he explains, the way you solve this is just how you would solve a 7 by 7 or a 5 by 5. Of course, you need to be a bit more patient.
[H/T: Kenneth Brandon]