Are there any tutorials out there that discuss how to do the "smart mapping" where you only have to texture one side and the other one is done automatically?

Not that I know of, but you should ask the texture forum here and the UVMapping forum at RuntimeDNA.

If your using UV Mapper, all you have to do is select 'Planar' or 'Box Map', then 'Don't Split'. This will give you a map template showing one side of the object only, but the texture map will be applied to both sides. This option isn't available for other kinds of mapping (in UV Mapper) There's only one problem with doing it this way. Often the reverse side of the object maps upside-down and the coordinates need to be flipped. mac

you could always just take the other side and move it into the same position on the template as the front side. this way, when you paint on the front side, it appears exactly the same on the back side. select the front side, maximize. seect the back side. maximize. if you mapped it correctly, the front and back side should now both be exactly matching each other. then you can shrink both down if there are other pieces left.

Thanks for all the replies. I'll give it a shot and see what happens. :)