Many travelers are not warming up to the idea of a virtual strip search as opponents of full-body scanners still insist they are an invasion of privacy, could cause health risks and question their actual effectiveness.

Airports started slowly installing the machines last year. But after the failed Christmas Day bombing attempt, the government immediately started ordering more of the expensive and controversial machines to be placed in various airports throughout the country as soon as possible. 

According to a report by USA Today, the Transportation Security Administration spent over $80 million on about 500 machines. The TSA plans to add another 1,000 machines by the end of 2011. 

Source: USA Today