Paraphrased summary from real dialog with a client:
Client: "We want users to have a 2nd password for our new intranet."
Consultant: "But you'll be using Windows integrated security already"
Client: "Right, but our users need to share their Windows usernames and passwords for other purposes, and we don't want someone else to log in to the intranet as someone else and see sensitive information."
Consultant: "You wha-- *choke* *snort* *cough* *spills coffee* *grasps holy amulet of network security*
Does anyone else see the fault in that reasoning? Holy crap. Welcome to the year 2006. This isn't a mom-and-pop shop we're talking about here either.