In case you were ever wondering how to make a felt ball, my method is very simple.  

1. Start crocheting a hat in Cascade 220.  

2. Be called away by some emergency in the house and stick said hat and ball of wool in your cardigan pocket.

3. Forget that it is there and wash said cardigan on hot.

4. Have the results be discovered by your husband whose response will be "(insert your name here).  Did you wash an unfinished hat again?"