I wanted to do a Doctor Who coaster as I've been a lifelong fan of the madman in the box, but I didn't want to go the stereotypical route of making yet another TARDIS (since I've already got two of them on here already). I therefore decided to go a wee bit more obscure and make a coaster bearing the Seal of Rassilon, founder of Gallifrey and father of the Time Lords, worn by the Council and armed forces of Gallifrey even now. It was interesting to make and hopefully you'll enjoy it too. It has holes in the back to take 3x5mm neodymium magnets or to act as wall fixings.
This coaster is also available, printed and assembled, in my Etsy store - www.etsy.com/uk/shop/enterprisexddesign