I borrowed a book last week from my local La Leche League with games to play with your baby. There was one in there about teaching climbing and physical movement by piling all your couch cushions and pillows in the middle of the room and playing fort or mountatin climbing with your baby. We were having so much fun with that!
What they don't mention is that if you have hardwood floors, you may want to first lay down a foam mattress. Maggie fell off the mountain :( Onto her head on the hardwood floor. So as Daddy got home, he didn't get to see what fun we were having, he just heard the screams. Poor Maggie and poor Daddy.