Attached Link: http://www.renderosity.com/viewed.ez?galleryid=104973&Start=25&Artist=aprilgem&ByArtist=Yes

I no longer have the model I made or the software I used to make it, but if you can get someone to model you a twisted and distorted teardrop, you could make fire like in the picture I linked. Essentially, what I did was make a teardrop in Amapi (sphere and cone merged), then twisted and distorted it in Amorphium (or you can try ZBrush instead). I imported the resulting 3D "flame" model into Bryce and used the fire material. Haven't tried the metaball way, so I don't know which is better or easier, but the flame model worked great for me.