best invention?

Some of the public restrooms here are just amazingly posh, like the one I used last week while I was in Roppongi Hills. My stall was spotless and roomy and completely enclosed, with stainless steel fixtures and what looked like hardwood walls and doors. There was also a baby seat, a compact, perfectly-shaped high-chair, tucked neatly into the corner, with a sticker of instructions (make sure the kid can't climb out, don't leave him in there and go to the sink to reapply makeup, etc.). Mothers who remember the infant/toddler years (my memories are a bit fuzzy) will appreciate how great this thing is. Imagine not having to hold your baby and pee at the same time. As for privacy, well, I can't imagine what could be invented to help us get that back.