NaDa

NaDa™ is a new concept. A thought, really. It is very light : 1 byte. It doesn't take long to fetch. It doesn't take long to understand. It doesn't disturb your habits nor does it makes you feel insecure. It is a reassuring piece of software that does nothing, and does it very well. And that's a lot!

http://www.bernardbelanger.com/computing/NaDa/