What types of interesting traffic would you permit or deny based on the uniqueness of your organization?

Interesting Traffic on an Internetwork
“Interesting Traffic” is defined as incoming or outgoing network traffic that requires an access control list to either permit or deny network packets to source and destination addresses.
Imagine your current organization is undergoing a physical reorganization of its network infrastructure. All workstations and servers (private and public) would be placed behind a firewall:
What types of interesting traffic would you permit or deny based on the uniqueness of your organization?
Are there any improvements regarding your subnets that could make the configuration of access control lists easier?
Considering segmentation between the private (inside) side of your network and the outside (WAN) network, as well as a layered security approach, what types of firewalls (and other security tools) would you use, and where would they be replaced within the organization? You may use a fictitious organization if you wish.

Last Completed Projects