What’s almost as good as a child that doesn’t make any mess (yes, yes, I know that such a child doesn’t exist)? A child that cleans up after him or herself after the mess is made of course.
You’re probably thinking to yourself that the second case is about as likely as the first, but if this rideable vacuum cleaner featured at Yanko Design is any indication it might be more likely than you think. I expect the fact that it looks like a slug (thankfully without the goo) will certainly help too.
Now, if they’d just release lawnmower, snowblower and hedge clipping variants I think we’d be good.