Section 2.5.5.2 of RFC-4291: IP Version 6 Addressing Architecture describes what in IPv4 terms one might call a super-network prefix that does exactly that: map the existing Internet onto an infinitesimal corner of the huge IPv6 address space.

When I first read the article title, I interperted it as some company had invented a roller coaster that was designed to keep the sum of the forces to zero, i.e. so you could ride it with a beer mug and no beer would fall out! -Chris