Well, I think that's best answered by you. What sounds the most interesting? A hobby should be something you enjoy doing, not something forced. Though honestly, drawing and writing would probably be the two easiest hobbies to get into, since you can do them at home without having to really purchase anything or devote major amounts of time to it. Besides, I always suggest people write, as it's a blast and, for me, helps me sort out my feelings and emotions in a safe, confidential way.