Recon scripts for passive DNS lookups and other basic recon of IP addresses Most of these require an API key, register an account with that service to get a key, then add your key to the script (if you're lazy like me) Or better yet, store those keys in a password safe and interface your script to that
For a full writeup, check the Internet Storm Centre diary at: https://isc.sans.edu/diary/Using+Passive+DNS+sources+for+Reconnaissance+and+Enumeration/28596
Also, recon scripts by DNS zone: https://isc.sans.edu/diary/DNS+Recon+Redux+Zone+Transfers+plus+a+time+machine+for+When+You+Cant+do+a+Zone+Transfer/29552