(Lynn: yes....if I cross-stitched I'd really be tempted to do one in cross stitch like a nice sampler, and frame it, and put it up in my office....my dad had one of those signs years ago in his office at Akron (so I think I come by my messy office-ness honestly). I think his said that a neat desk was the sign of someone who wasn't DOING anything...)
I found more geeky knitting. (Oh, I'm sure there's gobs of it online, I just haven't looked much lately.) This one has to do with emission spectra....which I vaguely remember from basic chemistry. (I'm more likely, these days, to work with things like absorption spectra: what wavelengths of light are absorbed by some plant pigment)
Anyway. I think this kind of thing is really cool even if I have to think hard to remember what it's all about: examples of emission spectra scarves (and you can buy one from there, if you prefer to buy a scarf over knitting one). What I saw first, though, was the emission spectrum scarf generator. (Example given is for Yttrium, just because I've always liked the name of that element.)
It's fun to play around and see what different patterns you get. They all pretty much follow the rainbow but the width of the lines and where exactly the lines fall (and what gaps there are) depends on the element - as I vaguely remember from learning about these before. You can choose any chemical element you like and make a scarf based on it! It even gives you a row-by-row pattern so you can get it to come out just right.
There is, however, no Element of Harmony you can make a scarf off of. Then again, you could probably mock one up: black background with narrow lines grouped to represent each Pony.