During my break: I learned squash (so much fun - can't get enough of it, and it's so good for you), studied Spanish (lovevto travel in Latin America), learned a bit of Scala (not really that much, to be honest), took some salsa dance classes (tough, but so much fun. Met lots of new friends), and did some Lynda courses on video editing (for making fun travel videos). I also spent a week and a half doing a road trip through southern France and Italy. Read a lot of books that were on my "someday" backlog - almost 0% TV!
As someone else mentioned, the quasi-unstructured time in the day was so refreshing. I loved just doing some random boring errands, bumming around the coffee shop talking to people, taking a long walk in the park with the dogs (I live in NYC)
I'll tell you: I'm 2 months i to my new job (technology job at a startup), and I really miss the feeling of this unstructured "regular life", or whatever you want to call it.
Cherish it, but don't overdo the planning, as it'll stress you out!
All the best!