Google data center search tool

Have you ever had a problem where a client can't see any changes to there placement in Googles ranking. Apart from clients possibly being logged into there personalised Google search account, the most likely cause is because Google have yet to push out to the latest index to the data centre your clients searching against (Google have lots of different data centers and indexes). To help you see any difference you can use this website http://www.mcdar.net/dance/index.php which will allow you to check all of the data centers for comparison.

Thanks to Mark NG for pointing this out.