create an omni emitter colour the particles bright white, add a turbulence field for some variation, play for a while, render in the hardware render buffer with a black background.
That's a basic starfield. won't be very interesting but if you want to make it more complex you can look at applying pictures of galaxies etc onto planes then placing them around the scene. Or you can simulate them with particles/fluids. experiment!
Alan
Technical Director - Framestore
Currently working on: Your Highness
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