What happens when you take some stalks made from twisting, tapering extruded ellipses and have them bulge out and then taper together to a point? Well, this is what you get. With an overall shape of a stereotypical candle flame, what else can I call it?

This OpenSCAD object is my favorite at the moment. Like most of the others I've based on twisting and bending columns, it's made up of many thin slices stacked on top of each other and thus takes a while to render (17 minutes on my 3.2GHz i7). You can tweak the number of columns that make it up between 3 and 15 or so, though below 5 the bottom separates making it a bit hard to take off your build plate without a brim or raft.

A photo for a 9-column flame is also shown here. And I've been experimenting with forming an 11-column version of this around a cylinder and putting an LED unit inside. I'm still trying to find the best type of filament to do this that doesn't block most of the light.