Additive Alpha, and Self-Illumination materials

I’m building a ‘Ghosty Tree’ which requires use of non-specular, alpha-channel planes. It took me ages to figure out how to do this (D-Var = 0, Alpha set to negative (yellow)!).
However, I need:

  1. some of the materials use to be additive-alpha
  2. other materials to be self-illuminating?
    How does one go about doing this without ruining the alpha-non-specular element?
    Again, huge thanks for any help.
    Dene
    P.S. This is without doubt one of the friendliest, most informative forums out there, and I appreciate it more and more every time I come here (sorry - too much caffeine makes me emotional <sniff>).

1 On each channel, if you want the texture to affect the alpha in an addititive sort of way, in the Matrial Texture MapTo panel, enable alpha, and change Mix to Add. 2. http://wiki.blender.org/index.php/Special:Search?search=self-illuminating&go=Go 7th link is a tutorial I wrote for Max user converting to the OTF (One True Faith). We call it Shadeless.

Many thanks!
Worked perfectly. And really nice tutorials, by the way!