We’re working on an data center design for a customer, and they’ve dropped in two ISP links - each with it’s own managed router and public IP space off one of the Ethernet interfaces.  The idea is that they want to use the Internet links in an active-passive setup without getting their own IP addresses to avoid running BGP with the ISPs.  To top it off, the headend of their control is an ASA cluster, so we wind up with two interface on the Internet to treat with a local security level.  Oh, the joys of doing network design.