The Fireball brand glow plugs have been around since 1947.
They are still made today. I think the business has been bought and sold several times now though.
Swanson Associates claim they have been making them since 1947, but I don't know if it is true or not anymore. It may be just marketing.
<span class="f"><cite>http://www.rsmdistribution.com/fireballglowplugs.pdf</cite> </span>

http://www.radicalrc.com/category/Glow-Plugs-171