It probably sounds crazy, or something else to add to your "must do" (aka stress list). But ...
Quick background: my daughter wants to be a midwife. She's 15 and I homeschool her. I was looking for things to get her out of the house (I telecommute so we're together 24/7 and it's sometimes too much.) I found out she could volunteer at the Children's Hospital as a junior volunteer. Well, I couldn't have her do something I wouldn't do myself, right? So I added it to my "must do" list. Doing the orientation, health screening, buying vest, and getting badged were added stresses, but the volunteer work I'll be doing negates all that and more.
I get to "baby-hold" in the nursery. The lights are dim, we sit in recliners, and we're admonished not to hold a baby for 5 minutes. We're to hold the baby for "awhile" - preferably until it falls asleep. It doesn't matter if the entire nursery is screaming - you only worry about the one you're with.
It was utterly amazing. The tension just rolled off me. No cell phone buzzing, no teenage kids or husband demanding attention, no work deadline to meet, and no hurrying to get to the next item on a list. I have to sit there, put my feet up, and focus my whole world on one tiny little baby. I also - trying to think ahead - scheduled my volunteer work for late Friday night which is when I would normally have to be available for kid drop-off/pick up at friends (before/after volunteered hours) so there's no conflict or stress about being out and about and no hurry if I'm running late.
It won't work for everyone, but finding this little oasis of calm where I'm helping someone else is one stress-buster I'm glad I found. I think the key was how I scheduled the hours and the "job" I get to do.