Seconded on the bodyweight stuff, I'm no where near some of the stuff you can do, handstand push-ups, muscle-ups, they are more than just strenght too, you need balance and co-ordination to pull them off right.
There are other options too, sandbag training, sledge hammer training, movenat stuff - going out to the woods and throwing rocks, carry trees etc.
You know all those pictures of Adam and Eve where they have belly button? Think about it..................... take as long as you need........................