This is indeed why I live in the country. I don't have kids, so I guess I should focus more on yard sex :p
Me and my wife love the quiet, the the privacy. I grew up on the farm next door so I guess that isn't all that suprising though...
I agree with having both the post date (optional?) and the markdown option, I like the idea of being able to toggle markdown, you could still default to plain-text and so preserve perfect backwards compatibility. Also I can't help but wonder about expiration dates and the ability to edit or delete, maybe have an optional password?
I've never seen one before but I want one! Although I can't imagine it would be good to keep around electronics.... I envision making a band out of it and wearing it like a bracelet, then I always have something to play with when I am bored!