If you want a serious answer, then I can give one. I did a mini research project as a undergraduate on the feasibility of mind-control technology.
My conclusion was that while there was certainly scope for tech involving neural implants, it's basically impossible to do this with 'mind-control beams' as commonly imagined (i.e. working on a normal person with a brain that doesn't already have some sort of receiver device embedded in it, or at least attached to the scalp so that it can stimulate neurons up close). The main reason being that non-ionizing radiation, such as the radiation in the mm-cm wavelength range used for mobile phones, basically does not interact with living tissue unless the intensity is high enough to cause a noticeable warming.
Now mobile transmitters are usually very high up and also located in fenced enclosures, so you're not just going to walk in front of one and get start to feel like you're getting cooked. Even if this did happen through some freak accident, you'd certainly notice it, and it's also hard to see how any sort of signal (let alone a 'suggestion' or 'command') could be encoded in a physical interaction as entropic as simple heating.
