Update: Also see this post, with a more comprehensive video.
117 words in 40 seconds = 174 wpm
I didn't get this particular voiceover gig, but this was one of the rare potential clients who granted me permission to use the submitted audition for my own marketing. :-)
134 words in 38 seconds = 212 wpm
This example is boilerplate legalese, which would typically be processed further to remove all breathing and other pauses, words shortened and volume reduced, to yield mumble-ese. :-)
86 words in 22 seconds = 235 wpm
The portion from 0:04 to 0:26 is a tad insane, but the client insisted that he said the same things in Dutch; in fact, we had to trim about ten words that I just plain couldn't fit. :-)