I ordered a package that was shipping through UPS and when I called I was dismayed that there wasn't a way to enter my tracking number (It was 15ish alpha-numeric characters) besides speaking. So I thought "Okay, AAyyy--Fiivvee--Geeee..." I was about half way through slowly saying the tracking number when I was interrupted "Package not found, try again?"... Okay. "I must have to rattle this off pretty quick" I thought, so I blew threw it. It immediately found my package, told me where it was and when it was expected to arrive.
It was amazing. Voice recognition was good enough that UPS deems it fail-safe enough to have it be the only way to find a package by phone. That was the first time I really thought there might actually be a chance for an almost fully speech operated phone without a traditional UI.