Is there a way to activate or modify an effect during a clip?

like with key frames or anything?

I notice in history, it refers to key frames added or

modified, but I dont see key frames any where.

Also,it would be nice just to be able to copy or

drag an effect from one effects rack to another.  

Is that possible?  I dont even see a "copy" option

in the effects rack.  I dont want to save the effect

and then apply it unless that is my only option?
Thanks