Streak Particles

I think there should be a new particle type called a streak. It would essentially be a particle that had a trail that would simulate motion blur to create things like sparks, embers, etc. This has many advantages to regular motion-blurred particles. For one, you could see the "motion blur" in the viewport to get a better feeling of your final animation. This would also be much quicker than regular motion blur when it comes to rendering. Houdini already has something like this as shown below.