Nikto is an open source web server scanner which performs comprehensive tests against web servers for multiple items, including over 6400 potentially dangerous files/CGIs, checks for outdated versions of over 1000 servers, and version specific problems on over 270 servers.
In addition to the usual list of minor bug fixes, 2.1.3 contains some new functionality and improvements,
Interactive scan pause feature
Metasploit logging (courtesy Ryan Linn)
Command line proxy specification
Scan status reports guesstimate of time remaining
Many updated software versions