Sudoku
The objective of the game of Sudoku is to fill a nine-by-nine-space grid with numbers so that each column, each row and each of the nine three-by-three sub-grids that make up the larger grid contain all of the numbers from 1 to 9. The puzzle is already partially filled in when the person begins to play, and usually each puzzle has a unique solution. Researchers have found that Sudoku increases IQ by promoting spatial intelligence and memory function.
Crossword
Another way to increase your IQ is by working crossword puzzles. Like Sudoku, continued crossword play has been shown to increase spatial intelligence, which is a factor in your IQ. In addition, because crosswords require you to have a good vocabulary, your IQ will increase as your vocabulary skills grow.
Computer Games
You might not believe it, but even some video games have been found to increase a person's IQ after prolonged use. Research conducted by scientists at the University of Rochester and published in the science journal "Nature" suggests that playing first-person computer games can positively influence IQ by increasing visual attention skills, an important contributing factor to IQ.