Vat of Knowledge

This is a utility no admin can be without.  This is a third party app, as opposed to the nbtstat command.  When run, it will show you detailed information on your network, and machines that are alive on the subnet you are scanning.  It also provides MAC addresses etc.  Download here.  Website here.  The syntax is as follows:

nbtscan 192.168.1.0/24

And the results look like:

Doing NBT name scan for addresses from 192.168.1.0/24
IP address       NetBIOS Name     Server    User             MAC address
——————————————————————————
192.168.1.2      WHS              <server>  <unknown>        00-19-66-52-86-72
192.168.1.127    XANETH-DELL      <server>  <unknown>        00-11-95-bd-ad-0b
192.168.1.129    NATALIE-PC       <server>  <unknown>        00-19-d1-0e-61-3a
192.168.1.138    HTPC             <server>  <unknown>        00-13-46-97-9c-dc

Comes in handy when you’re trying to track down the MAC of a particular machine to find out, say, what port it’s connected to on your Cisco Catalyst (sh mac-address-table address 00:00:00:00:00:00).