Logic puzzles with numbers

Number logic puzzles are grids where the numbers are the clues, and often the answer too: you write in digits that add up, follow an order or fit a pattern. There's hardly any arithmetic involved. The work is figuring out which number can still go where. Kakuro and Calcudoku are about sums, Futoshiki and Kropki about which number is bigger, Hidato and Fillomino about counting. You can play all of them here, free, in your browser.