Many airports do not have these scanners in them at all, and if they do, only at one or two checkpoints. Know your airports, choose your checkpoints wisely, and avoid the scanner altogether, thereby escaping the supposed "random" selection. Are the TSA intelligent enough to employ a proper random sorting algorithm for their highly-skilled employees to use on the fly? One wonders...

And if you haven't already heard, 11/24 is Opt-Out Day:
http://www.optoutday.com/