81.   Last month, a consortium of government and industry officials tested the smart car concept on a specially adapted section of interstate highway north of San Diego.

82.   Just as the interstate highway system looks like a web, with many interconnections, backbones are not so simple.

83.   Like the interstate highway system, a national grid could eliminate bottlenecks and encourage competition.

84.   Many property owners, however, oppose rail routes down the middle of interstate highways because they force the roadways to encroach outward.

85.   Meanwhile, the remaining water, now partly channelized, flows past shopping centers, industrial parks and interstate highways.

86.   Most of the restaurants have long since disappeared, done in by the Interstate highway system and the rise of national chains.

87.   Nor do they go to their three-limo garage, load up the family bullet-proof sedan and jump on a nearby interstate highway.

88.   Nine states, including California, are poised to eliminate or raise their speed limits on interstate highways in the coming months.

89.   No need for interstate highways at all.

90.   Once these one-time effects recede, the Internet will take its place alongside the airplane and Interstate highways as just one of many reasons productivity continues to rise.