NetList is a small networking and security auditing script I wrote in Ruby. Given a search term, it will query the ARIN database for an organization and all of its related networks. This can assist a pen tester in finding out which networks are owned by the target, and noting them for a later scan and audit.
$ ruby netlist.rb facebook
[!] Starting NetList script...
[!] Found 3 organizations matching your query, "facebook".
[!] Starting network lookup queries...
----- FACEBOOK (FACEB) -----
* UU-65-201-208-24-D7
65.201.208.24 - 65.201.208.31
----- Facebook Inc (FACEB-1) -----
* FACEBOOK-CORP
2620:10D:C000:: - 2620:10D:C0FF:FFFF:FFFF:FFFF:FFFF:FFFF
----- Facebook, Inc. (THEFA-3) -----
* TFBNET3
66.220.144.0 - 66.220.159.255
* TFBNET4
74.119.76.0 - 74.119.79.255
* TFBNET1
204.15.20.0 - 204.15.23.255
* TFBNET2
69.63.176.0 - 69.63.191.255
* FACEBOOK-IPV6-BLOCK-1
2620:0:1C00:: - 2620:0:1CFF:FFFF:FFFF:FFFF:FFFF:FFFF
* FACEBOOK-INC
173.252.64.0 - 173.252.127.255
[!] Done. Enjoy!
$ ruby netlist.rb nasdaq
[!] Starting NetList script...
[!] Found 3 organizations matching your query, "nasdaq".
[!] Starting network lookup queries...
----- NASDAQ (NASDA-4) -----
* NASDAQ313-245-32
12.148.245.32 - 12.148.245.63
----- NASDAQ Stock Market (NSM-28) -----
* SAVV-S259211-0
216.90.143.224 - 216.90.143.231
----- Nasdaq Stock Market, Inc., The (NSMI-3) -----
* SAVV-N05736-0
209.144.94.88 - 209.144.94.95
[!] Done. Enjoy!