Retty is a tiny tool that lets you attach processes running on other terminals. so you were running that mutt outside of screen at your home machine and now wanna check your mail? attach it with retty, do whatever you want, detach it again and everything is as it was before. you don”t have to run them all in screen just in case.
note that the tool is only very lightly tested, so take some care. always check first if attaching given application works before you will do it for real.