snoopy.pl is a simple SNMP scanner written in PERL, and making use of the Net::SNMP module. It will scan a list of hosts, and report the system id back if a valid community string is found.
You can download it from the following link: https://packetstormsecurity.com/files/download/24705/snoopy.pl
Source: https://packetstormsecurity.com/files/24705/snoopy.pl.html