Sorry for the pun.
I'm adding some pictures here for posterity though they are also at:
http://www.facebook.com/#!/media/set/?set=a.255248927830966.60189.204533646235828&type=1
This is a new block type I'm playing with. There is still some tweaking to do and I'm not really happy with the animation... but it may have to do for now. I'll probably end up playing with the effect and the animation 50 more times before I'm through but at least the infrastructure will be in place.
Just a bunch of big flame blocks:
I added a few different flame blocks to a firewood object and then also put a big flame block on top of the whole thing:
A bunch of different flame blocks in a tree: