Retrobrite is easy and cheap. I just did the white keys on my sol-20 keyboard.
Cost about $5 for a big bottle of 40% peroxide (you can mix it easily down to 10%, but save money by buying 40% over 10% since the cost difference is about $1).
You can buy OxyClean packs, but I have some to spare and then you need thickener from the supermarket like arrowroot.
Anyway used a UV sterilizer light that I have, maybe if you pickup one up that is yellowed I can bring my UV light and some OxyClean and stuff and we can retrobrite it in May at the workshop.
--- In firstname.lastname@example.org, Evan Koblentz <evan@...> wrote:
> > You can un-yellow with retrobrite.
> I prefer one that's not yellowed in the first place.