Comment by op4

http://www.whatsmydns.net/#

http://www.whereisitup.com/

http://multirbl.valli.org/lookup/

http://www.unlocktheinbox.com/blacklist.aspx?st=BL

http://www.myiptest.com/staticpages/index.php/DomainKeys- DKIM-SPF-Validator-test

https://github.com/rackerhacker/MySQLTuner-perl

http://www.pantz.org/software/mysql/mysqlcommands.html

http://www.hirensbootcd.org/

http://speedof.me/

http://loads.in/

https://www.pingbrigade.com

http://servermonkeys.com/els.php

https://www.passwordlive.com/

http://dnsviz.net/

http://ddecode.com/phpdecoder/

http://browsershots.org/

http://www.subnetmask.info/

http://bullshitipsum.com/

http://www.tuxradar.com/termbuilder (for the newbs)

add as link to edit a site live (if needed) javascript:document.body.contentEditable='true';%20document.designMode='on';%20void%200

http://www.cc.gatech.edu/~partha/diffprobe/

http://amon.cx/

http://www.internetpulse.net/

http://www.internettrafficreport.com/namerica.htm

http://relayservices.att.com/content/2/im_relay_3.html

http://www.puppetlabs.com/

and of course... http://oldspicevoicemail.com/