How to buid a piece of hair?

The slimest pole is 0.01m. But a piece of hair is less than 0.001m slim. How to create it with prim instead of texture?

/me imagines a 150,000 prim wig and screams.

You can fake it by doing something like hollow a cylinder, set the transparency on all but the hollow to 100% (you'll need to either apply transparent textures or use llSetAlpha from a script to do that, for some reason the editor stops at 90%), then shrink down the hollow (and then shrink the cylinder to make the hollow even smaller). You might find that strands at realistic hair sizes are a little hard to see.

You might also like Torley's gentle introduction to tiny prims, http://youtube.com/watch?v=m6XqQM9hgB0 or http://vidtuts.s3.amazonaws.com/second-life-tutorial-how-to-make-tiny-prims.mp4

Yes, nanoprims are possible with the right amount of abuse. Hopefully your goal is just a three-strand-comb-over. (o.o) Otherwise, you will not be liked for that 150K prim do that takes the whole sim down. (>_<