http://www.hashemian.com/whoami/
What is my IP address? What is my DNS info? Who is my ISP? What is my Whois info? what are my browser headers?
Ever wondered what your computer looks like to the outsiders?
Here is some information about you, such as browser type and IP address, and
some information about us, such as server type and IP address.
There are also Whois and DNS dumps on your ISP, if available.
Actually, "whoami" is an old unix command that tersely prints the effective user id.
The "id" command is more useful, but whoami has persisted throughout the years.
And FYI, the unix/linux command to get your box's IP info is "ifconfig". The equivalent Windows command is "ipconfig".
Need DNS information on a domain? try whois.
Need MX record/mail server/domain email information for a domain? try MX Record Lookup.
To Ping your IP address or a host, try Ping
