I've made a nice little Drupal module for Stack Overflow. Currently it enables display of the Stack Overflow.
In the future I'll add the ability for each user to fill in his Stack Overflow/Server Fault/SuperUser ID and have his flair(s) show up on his user profile.
You can see the module in action and find more details in my blog post about it.
Bugs, suggestions, etc. should be posted in the issue queue.