Possible? I have a plane, and I’d like to have a different texture on each side of said plane. Is it possible, or do I have to double up on polygons?
Thanks, in advance for any info! 
Sorry i missed the “different” previously.
As far as I know its not possible!
different texture requires different geometry as you must assign the different triangles to different materials in the modelling application (or the same material and UV mapping, but even in that case, distinct geometry is required)
I sugest to use an application to mapping the polygons.
I use Body Paint.
Then on Body Paint, yopu can tell to each polygon which texture is on it, or a single texture and match with polygons.