A demo for BtRL came out recently:
BtRL is a modified total conversion of FreeSpace 2, using the SCP project, set in the BSG remake universe. The demo version includes a short two mission campaign, a hefty chunk of multiplayer missions and three flyable craft--the Colonial Viper Mk II, VII, and the Cylon Raider. Only the Mk VII is flyable in the single player campaign though. It does not require the retail version of FreeSpace 2.
Here's some sample footage of multiplayer combat, notice how it's quite different from typical FreeSpace 2 fare: