Bullet Trail techniques!

Hey all!
I’m writing this short post when i’m tired, but here is my little question!;
How would one create a “realistic” sci-fi bullet trail. Textured planes are too 2d for my liking, and combining them doesn’t make a difference. I have one method involving a sort of cone shape, but again it seems too different :S any ideas?

While Planes would work well if only align correctly towards the Camera, how about a simple Cube stretched slim and with a Normalmap (like horizontal Waves) combined with martinsh’s Water- and Glass Refraction? Of Course, just if you go for those stylish Ones.
If you are more up to the typical white, smokey Trail and don’r want it to be just a Plane, then how about some subdivided Planes with a sinewave-shaped Trail Texture and twisted so the Mesh gets a threedimensional Effect?

What sort of trail? Matrix style “waves”?
Or smoke, like from a missile?
Or just a streak?

Why not just a really thin cube, like C.A. said?

It kind of depends on what you mean by “realistic sci-fi”. If you want it to look like modern tracers, you can do it with 3 alpha mapped shadeless planes, with the face normals along the x, y, and z axes (you will never notice that they are 2D if you use 3 planes). Now, if you are looking for something more sci-fi… well I don’t know exactly what you want, so I can’t really say.