If you have time off, do something risky that you wouldn't do normally. Why? Because soon enough you'll likely be back in the normal swing of things and unable to take that risk.
I worked on an organic farm this past year for two weeks (through WWOOF) and it was probably the best two weeks of the year for me. It really opened my eyes to how food is produced and just how much humans have changed the landscape of the planet - well worth the effort
I spent 6 months at home and abroad travelling and WWOOFed for 3 weeks of it. Those 3 weeks had the biggest impact and resonate through my life even today, years later.
If you have time off, do something risky that you wouldn't do normally. Why? Because soon enough you'll likely be back in the normal swing of things and unable to take that risk.
Examples:
Work on a farm
Do the Appalachian trail (or similar)
Take the train across Australia
Learn to ride a motorcycle
Learn to play guitar
Etc Etc