I would think that the quadcopter or even a octocopter is the best way to "warfly"
There is already autopilot hardware/software (ArduinoAutopilot) out there on the market where you can plan a route,
whetever it is around the neighbourhood or longer distances ( depending on the battery life ) + a open sourve wifi logger module
another great way is hook up a raspberry pi to control the multicopter with linux running in the background (airodump-ng, kismet, thc-wardrive, whatever... )
great example here btw :)
http://code.google.com/p/owenquad/
i really like the concept of warflying :D
