I've sure this will have been done before on mumsnet, but this is just a little reminder for those of you who cherish your privacy....
Our baby monitors (standard tomy) are usually both off or both on, but the other day, for some reason, just the transmitter was left on. The next time I saw a good friend (who lives 8 houses down the road, a good 400m) she casually mentioned that her monitors had been left the other way around (receiver on, transmitter off) and she had clearly heard dh and I have a conversation. It was luckily something v innocuous and she'd quickly turned hers off (bless her). I was still mortified though. Made me think about all the things I say in the privacy of my home that would make my toes curl if broadcast publicly 
So beware!