UFO2000 is a multi-playable remake of
Microprose's X-COM: UFO Defense that uses
the Allegro game programming library. It can use the data files from original game, but does not require them.
Open source project that offer summary and download services on this page is a project that carry out their development work on other open source development sites. Their work is linked to this page via a feature called OFI, and their work is not carried out here on OSDN site.