Recycle a plastic jug into a play "shower"
Take a large plastic jar or jug, and with a small drill (or even a knife if you want) drill a number of holes running around the bottom rim of the jar. Fill with water and hold over the kid's head! Voila! You could use a large peanut butter jar or even an old milk jug. Use it in the shower for rinsing or playing, or in the pool as a toddler toy (older kids will probably love it too, but my 3yo and his younger cousins go nuts for it in the kiddie pool). I love it because it's a negative cost item: you've already got the piercing tool and you're recycling your garbage = less than no cost to assemble!