Kilandor and I have a fully running MySQL caching system (bypasses the entire generation of the page block if turned on thus effectively nullifies any load that's page related). The speed increases and load decreases are ... well, amazing.
(tested on 350.000 page portal, dropped load down two times, sped up site by 100%)
We call it supercache.
Can release it.
<a href="http://www.domenlo.com">Surreal Art</a>