Oh nothing in particular! I've always been very interested in the supernatural. Ghosts especially! When I first saw "canwll corfe", I was hoping it would mean something interesting. Since I was reading a book about hauntings, I'd figured I would. I've always been interested in culture and language and it had it all! Corpse candle? Harbinger of death? Old welsh? It was so unusual and foreign. I've used it as my username on every site I've joined since I read it.
Corpse candles? Elf lights? May I ask what led you to choose such a screen name, Tim? Is your family Welsh? Mine is Spanish, but from NW Spain, where a lot of Celtic folklore remains, including superstitions about wiil-o'-the-wisps (or marsh-lights) being omens of death or spirits of the dead. There are also the White Ladies (damas brancas), who encounter travelers near caves or fountains and force them to dance with or curtsy to them; if you refuse, they throw you into a thorn bush or plague you with goblins (trasnos).