I flew from DCA to Fort Myers, FL a month or two ago, carrying a crappy old Radio Shack Pro-92 scanner in my carry on bag, and the TSA-dork stopped my bag under the x-ray machine and stared at it for a good, long time. He finally asked me, "is that some sort of radio in there?" to which I answered it's a scanner... he gave me a bad look and continued to stare at it. Seeing that he was bound and determined to cause trouble, I finally pulled out my fire department identification and showed it to him, after which he was kind enough to let me go on my way AFTER a screener felt around in my backpack for a while (though oddly enough the screener never even payed attention to the radio - or anything else in particular!)
I guess it's a good thing I didn't try bringing my XTS3000 along!