Outdoor Tic Tac Toe Board. Interesting things to do out there in your backyard. So simple and cheap to make, and you could play them with your kids or family anytime. http://hative.com/creative-and-fun-backyard-ideas/
bucket table for the deck. this is a genius idea. you can store all the stuff in the table that you don't want to leave out in case it rains (citronella candles, pillows, etc.), then just grab it out whenever.