People tend to hate those Interactive Voice Response systems ("press 1 for sales... press 2 for tech support... etc.") and so do I. However I was recently impress with something that Verio does on 1-800-GET-VERIO. A man speaks the odd-numbered choices and a female speaks the even numbered choices.
This alternating voices really made it easier to concentrate on what they were saying.
It reminded me of my days on highschool radio station WJSV (90.5FM) where I was taught to always pair two strikingly constrasting voices on any program we produced. The easiest way to do this was to have one male voice and one female voice. The results was an audio presentation that was easier on the ears.
This kind of attention to detail is appreciated.