Music Bounce
Here is a fun little javascript program that lets you create squares that bounce around in a box. In addition to picking the color of each square, you can have each one play a note whenever it hits a wall. You can choose any of the 12 chromatic tones in an octave for each note, or choose no sound if you want. You can also create as many squares as you want, and start over by choosing to clear the board.
Color: Harmonic Interval: X Speed: Y Speed:
For Music Bounce, I needed to control the direction and speed
with which things travel across the screen. There are checks to
see if a square hits a wall, so it can bounce in another direction.
The game also plays sounds by incorporating audio files.