Travel – even around my own city. See all those places you have been meaning to visit.
What hobbies have you been thinking “I really want to…”. Now is your chance. Get your camera out and start taking pictures. Take some cooking classes. Learn a musical instrument. Take some classes in a language so when you get another 10 weeks off you can be prepared to travel to places you have always wanted to see.
Start a blog.
Take up cycling, swimming or a team sport.
Read all those novels in the pile by the side of your bed that you have felt guilty about picking up because it would distract you from your studies.
Visit friends or family you have neglected.
And finally, and the best option, do some voluntary work for an organisation or people in need in your community. Share your time with others in a positive way.