[Samba] samba machine$ accounts

[steve]

Hi
Is there anything special about accounts ending in $?

I ask because I've just installed the whole of Samba 3.6 just to get the 
net command to join a Linux box to a Samba 4 domain. Afterwards, the 
machine will be using Samba 4 for authentication and filesharing with 
win 7 clients. net ads join prepares a keytab with
  host/fqdn at REALM
  host/hostname at REALM
  hostname$@REALM
entries.

1. Can I have the net command without installing the whole of Samba?
2. Is this part of what happens during net ads join -Uxxx?
net ads keytab add hostname$

openSUSE 12.1
Thanks,
Steve