In what may not be tinfoil, Mark Odell reports in the Financial Times, a reliable newspaper, that in the UK at least, governments can turn cellphones into spy microphones,
If ordered to do so, mobile telephone operators can also tap any calls, but more significantly they can also remotely install a piece of software on to any handset, without the owner's knowledge, which will activate the microphone even when its owner is not making a call, giving security services the perfect bugging device. “We have inadvertently started carrying our own trackable ID card in the form of the mobile phone,” said Sandra Bell, head of the homeland security department at the Royal United Services Institute.
The source is “LONDON BOMB ATTACKS: Use of mobile helped police keep tabs on suspect and brother” (sub. req.) published Aug. 2, 2005. It is available on Westlaw (Westlaw acct. req.).