Henry Dudeney, a self-taught English mathematician and puzzle columnist, asked his readers to dissect an equilateral triangle into the smallest number of pieces that could be rearranged into a square.

Conceptualised as a vertical village, the 71-metre-tall Puzzle Tirana tower will contain 32,700-square-metres of commercial space, apartments, penthouses along with a hotel.

The Puzzle Alarm Clock ejects three different shaped puzzle pieces when it goes off in the morning and the only way to stop the sound is to complete the puzzle. It's a frustrating but effective ...