FSPort is a port of the FreeSpace 1 campaign to the FreeSpace 2/FS2Open engine. It now includes missions from the FS1 expansion pack, Silent Threat, as well as graphical improvements on the original media using FS2Open.
The Babylon Project is a well-known Total Conversion (standalone) mod based on the Babylon 5 universe. Official development has ended, but the community maintains its compatibility and adds enhancements via the Zathras project.
Diaspora is a single and multiplayer space fighter combat game set in the reimagined Battlestar Galactica universe, founded by former members of the Beyond the Red Line team.
Inferno is one of the oldest, largest mods for FreeSpace 2. Although R1 does not fully take advantage of the SCP graphical abilities, it features a considerable number of new ships and weapons, as well as a full campaign.
Wing Commander Saga is another TC mod based on the Wing Commander universe. It features several user-made cutscenes and has released a prologue and two tech demos. It is not being developed for a WCS-specific fork of the SCP engine.
Nukemod is an experimental mod by Nuke that takes advantage of several improvements of the SCP. It is still unreleased.
Beyond the Red Line is a Total Conversion based on the Battlestar Galactica universe. Notably, it was featured in Popular Science's "How 2.0" to build a homebrew flight simulator.