This site provides a detailed analysis of level 80 WoW characters. It can show you at a glance where your gear, enchants, or gems are weak. It also provides a very nice visualization of where you should be looking for gear and what raids you are geared to run.

The guild reports are downright awesome. Be.imba allows you to pull up to 40 characters in a shot by class or guild rank.

Some of these are not accurate because the character is in PvP gear.