Just go to unifycommunity.com then go to the wiki (snipets) and click on shaders. They have a window shader their.
AFAIK that shader is for simulating reflections (cube-map) in building windows as seen from outside, not semi-opaque glass. -Jeremy
There's a simple glass shader at http://unity3d.com/Documentation/Manual/SL-CullAndDepth.html. It's possible that will be enough do what you want, but you might want to get more involved with reflections and stuff for a more realistic effect. (But if you cut&paste the code there, change the first line to Shader "Simple Glass" { instead of SubShader "Simple Glass" { or else it won't work. That seems to have been a typo....) --Eric
Is there a shader that is totally invisible except for showing specular highlights? That would be what I'd want for a glass cockpit, for instance.