well, back to many years ago when I bought my first computer. At those days XT 8 MHz personal computers(8bit) were still at shops with 20MB hard disk and 5-1/4 floppy disk which I think was 360KB each. I couldn't hide my happiness when I bought a 386 AT(16 bit) samsung 16MHz computer with 2MB Ram(most computers had 640KB at that era)a 1.44MB floppy and 120MB hard disk(which was unbelievable at that time!) and of course a super VGA 14 inch monitor while still CGA monitors had customers!
A few months later intel announced that it has produced 386 @ 33 MHz with 32bit bus. It had been claimed in intel ads that this new CPU can review whole britanica encyclopedia in matter of seconds(unblivable!). Now high school kids start their computer vocabulary with GHz and GBytes. some even don't know what MHz and MByte means ;). How much fasters chips can be built? I seriously doubt that speed can go to TerraHz zone in next decade as it did from MHz to GHz. Because gates really can't be built
much faster with current technology . another problem is how to transfer these clocks? They need some sort of waveguide at chip level. How they are going to build them. Once I read somewhere that chip makers are considering using carbon nanotubes for this purpose but I don't know if this technology has actually been implemented in computers that we are currently using ?