NobleProg QueryCache

Allows users (everyone, including admin) to cache queries for a certain
time. It works perfectly with tables like 'system', 'variables', etc.
These tables hardly ever change during the standard application life.

Used on high traffic pages (5 million pages per month, 40000 users). Works perfectly well.

This module is useful if you fight with overloaded database server.

Features:

1. Uses CacheAPI or own file storage.
2. Rule based (regular expression) query selection.
3. Expires after certain time or on certain events.

You can download this module from: http://drupal.org/project/querycache