I have developed a wrapper to NCAT called rat (Router Audit Tool). It contains a simple tool (snarf) to download configurations and a report generation tool. The rat distribution contains the latest NCAT. The current version contains rules to check configurations against the NSA IOS Rules.
To download the latest production release, including the latest rules, please go to the Center for Internet Security at:
Here is a link to the postscript version of a presentation about the Router Audit Tool
Here is a link to sample rat output
Here is a link to rat documentation
Here are the the rat README file and rat INSTALL.txt file
Here is a link to the rules file
Here is an HTTP link to Rob Thomas' excellent security tools.
His Secure IOS config template inspired the creation of this tool
Also see Cisco's Improving Security on Cisco Routers