web-based dns, network, encoding tools

Looking for some websites that have some remote tools to do things like dns lookups, pings, port scans, string encoding, and more? Here are a few links to share. I tend to keep things like this on the “resources” part of the menu at right.

clez.net (saw this on SynJunkie today)
robtex.com (from clez)
serversniff.net (from clez)