When the babysitter is there go out for a walk or ride a bike. When a friend has time to watch the children, do some journaling or do a painting. Writing and art are very therapeutic. Light some candles too. This can be very refreshing.
Many fitness centers offer childcare.
It's a great place to get exercise. Smell the aroma, feel the warm cup, relish the taste. Contemplate the experience. Dress in a new way. Take out the fancy clothes you don't feel you can wear with the children in tow.