Key word is 'seem'. One hundred years ago it didn't seem that any one could conceive of the Internet, but here it is. With the always ascending technology curve time to meaningful technology advancements shrinks.
Nanotechnology should arrive in fifteen to twenty years. In thirty years it will be in nearly every industry plus industries not yet known.
One interesting place that nano-tech will be is medicine. Consider gradually replacing human neurons with engineered replacements that don't wear out or die. When the process is complete, do you have a human brain analog that lasts (effectively) forever? Is imortality within our grasp? (except for the "Hey ya'll, watch this" crowd)
/john
Good analogy. It paints a picture of a technology horizon that we can't see over, but can eventually reach.