Covers

CD Cover Central

The biggest and best cover site. Quality varies.

Mega Search

Search engine for all known cover sites. Very useful

Covers Archive

A bit like CD Cover Central, but with nicer design.

Vicious VCDs

Easy navigated VCD coversite with low resolution covers.

Hardware

Tom's Hardware Guide

The first (to my knowledge) of its kind.

AnandTech

Great site, one of the best.

Eric's Fast Graphics Site

As the name says, they test video cards. The first to preview G400.