I watched the tv show "Fringe" (Earthling episode) the other night and Derek was right, Lanza's voice was indeed used. It came right after a commercial break during the lab scene where Walter (the scientist) is trying to break some molecular code. Coming after the break, it was Lanza's voice that you heard first, singing "Una Furtiva Lagrima". It lasted about 45 second but was very effective because it was to the foreground at first, not the background. It was short but Lanza sounded great.

The scientist was totally stressed at trying to break this important code and he was playing Lanza on a record player. When someone came in and took the needle off the record, Walter became very upset, telling the person twice not to do that. But then the show continued. I really could not figure out why this aria was used or the voice of Mario Lanza. No reference to either was ever made. Nor was there any mention of this on the "Fringe" blog. Well, a few seconds of Mario on major networks is better than nothing.