What technique better to use to create a realistic fire?

Hello to everyone I have a simple question.
How to create a realistic fire. If I want to create a torch or camp fire I can use a particles system but still it is not the best way.
I need to create a good looking fire on a candle.
How can I manage such result. Maybe to use a pane with a movie that will always look on a player with a script or something like that?
Please help.

You would be correct, but instead of a movie, you could do a sprite animation on one image, and scroll between the uv space. Then make the candle fire a billboard