I wrote a pattern for a crochet hat quite a few years ago, it's not very well written, there's no gauge reference and it really was just a 'wing it' project. However, I've been fortunate to have the pattern well "favorited" on Raverly and other crocheters comment to make it easier for others attempting the pattern.
This pattern is licensed under creative commons with the stipulation that credit is given to the designer and it is clearly stated where the free pattern can be found. Enjoy!