BANS categories question

While I'm waiting for the BANS forums to come back up again, I'm going to ask this question here. If I've created a store using only a single category, like let's say DVD's and Movies and then later I decide I'd like to add a category, like collectibles, can I do that or am I SOL?

 

Very easy to add additional categories at any time.

 

I know it's easy if it has been set up as a multiple category store at the beginning. But I mean if it was initially set up as a single category store.