Never by calling the number, but I did try the magic bullet blender, purchased at CostCo. The little tabs would break off, so I replaced it with a similar Ninja blender, which is MUCH better IMO.
That said, I did participate as an audience member once! In a public speech class in college we had to attend a public presentation of some sort. One of my classmates was the "attractive female" part of the duo whose job it is to ask inane questions and pretend to be mightily impressed by the awesome demonstration. The teacher said it'd work for the assignment, so a few of us went to a taping. We were given instructions on how to clap to make it sound "fuller", when to clap, etc... we were also shuffled around a few times during breaks to "make the audience look bigger". Anyhow, it was some sort of in-floor radiant heating, not the typical "buy this overprice plastic gadget and we'll throw in not one, not two, but three 5 cent molded plastic widgets for just $5.99 shipping and handling [each]". Funny thing, though, they did give us a preview of the next product that they were supposed to try to sell... colon wipes. ugh. How do you get an audience to pretend to be excited about that!?!? And who'd want to be seen on camera looking interested in that!?!?