There is “_MainTex”, “_DecalTex”, “_BumpMap”, “_Cube”, “_ParallaxMap”, “_Detail”
That’s all I know about so far… is there any I’m missing?
I want to access the illumination map from the SelfIllumin/Diffuse shader, but I don’t know what to use… 
Oh… I got it! it’s “_Illum”
It would seriously be nice to see all these in one spot… I had to look all over the documentation… and wasn’t even there.
I found this thread though which is where I got my answer:
http://forum.unity3d.com/threads/111814-Illumination-offset