How LANs connected to Internet.
Doubling every 18 months means factor of four gains in 3 years. In 9 years, gain is then 43 or 64, which leads to 6.4 billion hosts. My intuition says that, it is much too conservative, thus by then probably every television in world and possibly billions of other appliances will be on home LANs connected to Internet. The normal person in developed world may have dozens of the Internet hosts by then.