It would be great if there was a way that we could associate our accounts with Twitter and when viewing questions and answers, could "tweet" it automagically. I know that there have been times that my question was not very straight forward and someone from twitterville actually came in and answered it for me...
This would essentially be a one way form of communication, maybe a button in each post that would allow you to tweet the post's link with a brief text input (obviously keeping the entire post to under 140 characters)
EDIT
you can argue that SO is not a social networking site, but that does not imply that there is no value or utility to be had there by some form of integration.