Rid Enum is a RID cycling attack that attempts to enumerate user accounts through null sessions and the SID to RID enum. If you specify a password file, it will automatically attempt to brute force the user accounts when its finished enumerating.
Winexe
Winexe remotely executes commands on Windows NT/2000/XP/2003 systems from GNU/Linux (and possibly also from other Unices capable of building the Samba 4 software package).
Nmap
Nmap ("Network Mapper") is a free and open source (license) utility for network discovery and security auditing. Many systems and network administrators also find it useful for tasks such as network inventory, managing service upgrade schedules, and monitoring host or service uptime.