MyNmap is a tool that uses Apache, PHP, MySQL, and Perl (designed to run on Linux, BSD, or other Unix clones) to display nmap network scan data for large networks. It is/has been used at organizations to regularly scan thousands of hosts with positive results. It has the ability to show changes over time (what is new or what has disappeared). It can display grids of what ports are available based on network, operating system, ports in common, etc. It can perform scheduled scans and export reports in CSV.