> To be more specific, I had the idea of seeing if it would work with
> just a row of lights in one place and you have to move your head
> to read it

I don't think so, unless you have more eyes than a spider and you
can select which one(s) is looking at the LEDs

The effect is similar to how a dot matrix print-head makes characters
with a line of pins. Where the pins struck the paper and made a mark
is the record of where they were. LEDs "print heads" use the principle
of persistence of vision, like a film strip or flip-book. Each frame is a
single static picture but run quickly in succession gives the impression
of a dynamic display

Bob Blick's Propellor Clock is a good place to start

http://www.bobblick.com/techref/projects/propclock/propclock.html

Google for "propellor clock" to get other examples, or eg "message
wand"

http://www.salient.com.au/led_MessBar.htm

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