VarAnimator...

VarAnimator is a slightly-hacked version of Sun's Animator class. For the Java animation above, you can perform the following functions:

• Click the mouse to pause/resume animation.
• While running, the "," and "." keys decrease/increase the speed. WARNING: do NOT increase the speed too much or Netscape will freeze.
• While paused, the "[" and "]" keys show previous/next frames.

With a slider...

I've added the Slider class by Adam Doppelt. You can turn it on with a

PARAM NAME="USESLIDER" VALUE="TRUE"

line in the applet tag. It "rubberbands" and you can decrease the speed (to 25%) or increase it (to 400%) with each drag. Again, WARNING that if you increase the speed too much Netscape will FREEZE.

Source...

You will need the two files VarAnimator.java and Slider.java.