Fill baby's high chair tray with water for warm weather splashing
Misty's found a way for her baby to enjoy some summertime water fun:
We are trying to not use the air conditioning, so things are really starting to get warm. My daughter is too young to really go swimming or use the water playset hack talked about on your site. But her high chair has a very deep lip, enough to hold about half an inch of water. I filled that with tap water, stripped her down, and let her splash around as she wants. It is amusing to see her reaction when she splashes herself, and her obvious enjoyment of the new experience.
I posted a picture in case that is helpful: http://www.flickr.com/photos/poushes/631973303/