<p>Indeed, there are <a href="https://stats.meta.stackexchange.com/q/505/930">pre-defined migration paths</a> (mostly because off-topic questions on this site are often of potential interest on SO or math.SE). I appreciate that users <a href="https://stats.meta.stackexchange.com/q/884/930"><strong>flag such questions</strong></a>, so that moderators can handle the migration quickly. You can also leave a comment to the OP, but in this case don't forget to remind him or her not to cross-post.</p>
