How to keep a child busy for hours in the summer: DIY: Giant Ice Cube Awesomeness - filled with plastic animals, dinos, and such. And I'm sure you could put in food dye before its frozen to color it like the ice block in the photo.
LEGOs suspended in a liquid soap dispenser. Fun to put out at a LEGO party or everyday use in your kids' bathroom! I'd probably search for a cuter dispenser, maybe more geometrical, but still such a cute idea! Also great for the Hand Sanitizer!