dns checker

Dns Jumper can change your DNS settings, Dns jumper is Portable and Freeware

DNS Redirector - Internet Access Filter, Splash Page Manager.

DNS Flood Detector was developed to detect abusive usage levels on high traffic

Lookup DNS information using a convenient graphical user interface

Backs up your current DNS server address and then changes it to Google’s DNS.

Net::DNS is a pure-Ruby DNS library,

A stand-alone multi-lingual spell checker for any Windows application.

Check the health of your disks or SSDs for free with Smart Disk Checker

MSDN article "Creating a Custom Spell-Checker with Word 2003 and Visual Basic

Mail Checker - Your mail box watch dog.