From news of the weird:

Unclear on the concept
An exhaustive report in December on CIA operatives who staffed the so-called “rendition” program, secretly transferring suspected terrorists from U.S. custody to foreign governments, revealed sometimes-sloppy undercover work by the agents. In one rendition, in Milan, Italy, covert agents failed to remove their cell phone batteries, thus enabling them to be electronically tracked even though the phones were off. Also, one clandestine operative left a clear trail of her whereabouts: Even though she booked herself at foreign hotels under aliases, she insisted that frequent-flier miles earned at the hotels be credited to her personal, nonsecret frequent-flier account.

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hummm.... now do i have to point this out that your phone can be tracked even if its TURNED OFF !!! you have to take out the batteries for them to NOT to track you...