I just asked a question on Stack Overflow and realized that it belonged on Server Fault.
Is there an easy way for me to move it?
If no one has answered yet, you can just delete the question and repost it. But this isn't ideal, because if someone was in the process of composing an answer, they'll be rudely told that the question doesn't exist any more and have no way to find your repost.
It's better to rely on the migration system. If a question is migrated, existing answers and comments are moved with the question, and if someone had started answering or bookmarked the original question, they'll be redirected to the new site.
The one thing you must not do is repost the question on the other site and abandon the original question. There must not be two non-closed copies of the question, otherwise it could result in duplicate effort as different people provide similar answers to the two copies. In fact, even if the question ends up closed but not migrated on the source site, you should leave a comment on the original, saying you've reposted. This is both helpful to people who've seen the question and want to see answers or were planning on answering, and for a moderator who might be reacting to a flag that was left before the question was closed.
Chances are it will be moved automatically soon, as soon as 5 community members vote to migrate it.
I cast a vote; 4 more to go. If anybody else wants to consider voting, here is the question.