The video above was made by PH3NOMDC and is a demonstration of bullet collision in his custom 3D engine. In the video he is using a map from Quake 3's Total Conversion True Combat. I had asked if he plans to release this for the Sega Dreamcast and low and behold I received a reply.
It seems we are finally on our way with receiving new 3D games for the Dreamcast. Hopefully PH3NOMDC will allow others in the Dreamcast community to use the engine so we can see a large library of games. Of course you can see his progress of his 3D engine for the Dreamcast at the following link.