Recap: How to empty a collection

I've been following this debate with some interest, but I think it's gone  
beyond a noob discussion.

Is there a noob answer to this question? There ought to be. I'm sort of  
leaning toward:

Q. How do you empty a collection.
A. You don't, you replace it with a new instance.

Q. What if you have references to the collection in multiple places?
A. Wrap the collection in another class, and reference that.

??