Question: how do you retrieve an email sent to the wrong person? 

Answer: haha.  You're screwed.  \n\n\n\nSorry, its just one of those situations that really sucks.  Once it's sent, it's sent.  If you didn't want the person to see it, you're S.O.L. but if you just didn't send it to the person you meant to, you MIGHT be able to go to the "Sent" folder in your email and see if it saved.  Good luck!
This question from the Yahoo Q&A forum is categorized in the topic: Health