Title : Reusing the Instance
Usage : Flash 5, Flash MX
Comments : This secret is known to experienced users. In the beginning i even used new symbol with the same shape having separate behaviour. What i mean to say is when u create an symbol(movie clip, button, graphic), there is no need of creating new symbols for the three separate behaviours. This will even reduce the file size of the movie.
Description : here are the steps:

1. Take any shape, here i took triangle.
2. Make a symbol of the shape and any behaviour. Then drag the new symbol on the stage for the library.
3. Now this symbol can be change to any 3 behaviours(movieclip, button, graphic) as required from the properties bar as shown in the image above.
4. Thank u for reading this small secret.