to be honest, hacking the circuitry may not be all that useful anyway in terms of gaining technological secrets
its amazing what can be done with a relatively low cost machine using off-the-shelf parts and technology
Put these two concepts (below) together and the result would be a cheap DIY communications spy. What it wouldn't have is range - but that should be fixable given scale. Any aerospace company would be able to overcome that
DIY Spy Drone Sniffs Wi-Fi, Intercepts Phone Calls | Threat Level | Wired.com
Southampton engineers fly the world's first 'printed' aircraft
Of course if you added solar power generation as well, then in some countries you would have potentially a huge range
And if anyone doubt the availability of 3D printers, a friend of mine has one for making scale-model railway locomotives. Cost him less than £10,000