Linux: nmblookup -A IP
e.g.
# nmblookup -A 192.168.1.238
Looking up status of 192.168.1.238
WIN2003 <00> - B
WIN2003 <20> - B
WORKGROUP <00> -
WORKGROUP <1e> -
Windows: ping -a IP
That was a good tip. Even though working so much on computers I always found something new to learn.