I think it's ready for general use now so here is my latest contraption! :)
It's a free scripted modifier plugin called 'Timewarp'. Its main use is for easy-nondestructive-time-remapping of animations. You get a curve that represent the object local time flow, similar to the PointCache's 'Playback graph' function.
A standard example would be a bullet-time effect. you can gradually slow down the animation of a few objects while the camera keeps moving at normal time. This without modifying the original keys or messing manually with a lot of EaseCurves.
So if you have a complex animation and you would like parts to speed up, slow down or even freeze or reverse it then Timewarp can help you do that with ease.
How does it work?
1 ) Select your objects and add a 'timewarp' modifier to them
2) Now nothing happens :) To initialize it press the '(re)create EaseCurves' button. This applies max's native EaseCurve to all animated properties, including materials, and connect them to the modifier's spinner.
3) Now if you play with the 'timewarp' spinner you can see your animation going trough time. You can animate this value to create a timewarp effect.
If you animate other parameters that weren't animated at the time you've added the modifier they won't be affected by the timewarp. Press the '(re)create EaseCurves' button to include them if you want.
When you disable the modifier on the stack it switches back to normal time, now you can easily adjust the original animation in max's normal linear time. When you re-enable the modifier the timewarp takes over again.
pressing the 'remove EaseCurves' button does just that, the object will no longer be time warped. (use this before deleting the modifier from the stack, if you forgot you can add a new timewarp modifier and use this button to remove the old EaseCurves as well)
It's all based on the 'EaseCurve' functions of max, this plugin automates and makes it easier to manage these.
Place script in 'max_root/scripts/startup' folder and restart max. If all went well a 'timewarp' modifier should be present in the modifier dropdown list.