One day, the internet will cease to exist.
Eventually some other more efficient and clever form of storing and sharing information will replace it, like the telephone replaced telegrams. And it will look like a quaint, old fashioned way to communicate. A mythological infrastructure rendered pointless by the living chips in our head that allow us to place thought directly into the minds of those we're connected to, from our eco-bubble body units that gave up the need for legs some time ago. Physical boundaries and distances having been replaced for centuries by a society that effectively exists as one in the common cloud of information and feeling and entertainment and learning. Like dust in a beam of sunlight, itself forgotten because we won't need light anymore. It'll be as irrelevant as horse-drawn carriages.
So the internet, a dusty, jammed, neglected collection of physical wires and satallites will slowly die, until the last forgotten computer light winks out, deep underground and alone. And the once flood of information and adverts and spam mail will fade out of existence as if it had never been.
When this happens, Lolcats will be the last thing that fades from the last cracked CRT screen..