Great animation engines for Javascript? - Javascript/Animations

I'm trying to implement a timeline based animation, where animations will be able to be:

• paused
• resumed
• fast forwarded
• slowed down
• reversed
• ...

Are there any animation/tweening engines for Javascript that could be used for such purpose? Or that would be highly recommended?

Hwlp would be great, especially as this really interests me! =)

I think all of these frameworks will do that for you (reverse isn't supported by all of them I see):

• jQuery: http://api.jquery.com/animate/
• $fx: http://fx.inetcat.com/manuals.php
• Scriptaculous: http://wiki.github.com/madrobby/scriptaculous/
• Yahoo! UI Library: http://developer.yahoo.com/yui/3/api/module_anim.html

I prefer jQuery.