You can have up to 999 balls, of different sizes and colors, bouncing around at the same time (if your hardware can handle it!).
All the screenshots referred in this text can be found on my website.
There are a lot of other settings you can change (screenshot 1 and 2), some of them described below.
There are two different modes in the screensaver which you can choose between: "Normal" and "Gravity" (screenshot 3 and 4).
You can change the physics of the balls in the screensaver, like friction (how much they slow down), gravity (how fast they fall), elasticity (how much they bounce).
You can also make the balls collide with one another. Make them rebounce if they have stopped (due to the friction).
There is even a possibility to have our solar systems nine planets bouncing around. Not very realistic but fun (screenshot 5).
You can make the balls leave trails behind them, quite a nice feature which creates interesting patterns (screenshot 6). The balls can also bounce around on your desktop (screenshot 7).
All these values and settings can of course be randomized and/or saved as presets for your convenience.
You can change the colors of the balls "live" by pressing the shift button in the "Random colors" or in the "Flower Power" mode.