I’ve been using OpenDNS for a number of months now, and I am a fan. My favorite features:

1. Faster DNS response than my ISP means pages load faster.
2. Typo correction – my .vom and .xom typos automagically get turned into .com for me.
3. They take an ‘as little as needed’ approach to asking for information from you.
4. Ability to request a DNS update for a domain.

If you haven’t been using OpenDNS, I recommend giving it a try.