Musipedia: Music Search

Musipedia is an editable encyclopedia of musical themes. It can be searched by entering notes or tapping a rhythm. Melodies can be identified even if the melody or the rhythm is all one knows.

Crossnumber Puzzles

The Crossnumber Puzzle Solver is an interactive constraint solver for number puzzles.

One can solve existing puzzles, create and solve new puzzles, share them with the world, or buy books with puzzles.