I’ve upgraded my old WP-Cache plugin to this one that I found on Digg.com today.
From the Digg.com Post:

Tired of clicking a link off the Digg front page only to find a crashed or mortally lagged site on the other side? Finally, Donncha (one of the main WordPress developers) has solved the problem once and [...]

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I just installed the plugin wp-cache. I’m not sure why more Wordpress users don’t enable this. From the Wp-Cache description:
WP-Cache is an extremely efficient WordPress page caching system to make you site much faster and responsive. It works by caching Worpress pages and storing them in a static file for serving future [...]

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