When you type sentences for her, Mimi will learn and say things back to you. The more you type, the more words she will know. She will probably start to say some pretty crazy things. Try telling her a story. She likes stories a lot. You can shift-click the green flag for 'Turbo Mode' if she starts getting slow to respond.
This was an experiment to see if I could make a searchable, inter-linked data structure using clones. Unfortunately, since each new word makes a clone, Mimi can only learn 300 different words. Updated to keep Mimi from linking the same words twice.