Google Public DNS is a free DNS (global Domain Name System) resolution service, that you can use as an alternative to your current DNS provider.
To try it out:

Configure your network settings to use the IP addresses

• 8.8.8.8 , IP for Primary DNS Server
• 8.8.4.4 as your IP for Secondary DNS servers

If you decide to try Google Public DNS:

1. Your client programs will perform faster DNS lookups using Google Public DNS.
2. Speed up your browsing experience.
3. Improve your security.
4. Get the results you expect with absolutely no redirection.

http://code.google.com/speed/public-dns/