This week the free app was Voice Candy.
It's a fun little, with perhaps not a very long life expectancy, unless you plan to use the alarm feature, but I do have one gripe.
My only criticism (yes, I am looking a gift horse in the mouth), it that when I record a voice and change the personality of the voice, I expect the recording to change as well.
From a pseudo code logic, it should be as simple as recording the original voice, and then playing it back through the personality filter.
Let me know what you think of the app - or if you think otherwise.