Do the two rooms that you want to network share a wall?

Nope, no shared wall, there's a bathroom in between the two rooms. Air ducts are also out of the question.

Basically, if I did run CAT-5, it'd probably have to go under the carpet (along the walls) in Bedroom #1, then go through the doorway into the bathroom, then along the base of the bathroom cabinetry, through the other bathroom door, into Bedroom #2. Really yucky.