There's Gold in That There Dead Air At a time when the nation's wireless companies are increasingly desperate for more airwaves to serve its customers, little-known NextWave Telecom Inc. has networks up and running in 26 markets but has never served a single paying customer. &lt;BR&gt;\&lt;FONT face="verdana,MS Sans Serif,arial,helvetica" size="-2"\ color="#666666"&gt;&lt;B&gt;-The Washington Post&lt;/B&gt;&lt;/FONT&gt;