If you have a good relationship with your manager, you could just be honest. I have a friend who adopted a baby a few years ago and was planning on quitting to be a stay at home mom - she went to her boss (knowing that layoffs were imminent) and asked to be laid off. She said if it would help someone else keep their job, she would volunteer to be in the group that got laid off since she would otherwise quit anyway. He was very nice and when the layoffs happened, she was one of the 3 who got let go and she got a nice severance with unemployment. And she probably saved someone his or her job.
I pulled this from thread +1eGje3Ul because I liked this story a lot. Unfortunately, my manager is totally different. Is it really possible to have such a good relationship with your manager here at BofA?