Light up pallet bed frame. I would use one more row of pallets to make my bed sit higher and paint the entire thing. I live the under lighting! Used this idea in my son's room reno.
51 Budget Backyard DIYs That Are Borderline Genius. Seriously this has some AWESOME ideas! A pallet and some rope makes a multi-person swing.
Paint slip n side: use washable/non toxic paint so it doesn't kill the grass