I don't know why this hasn't been done, but I'd like to see one of the PM companies design a "modular" system. Instead of a power meter that costs let's say $1500, how about you buy modules that are much cheap for maybe $500. You install these modules on several different bikes (this modules probably contain the strain gauges etc.). Then you have a device that contains the "brains" (PC boards, ANT+ transmitter) and batteries that costs maybe $1000. This device plugs into the modules and moves from bike to bike as you need. That way you can add power meters to other bikes without having to move around major components.