Wow, hard to believe someone pulled a comment of mine from '03 to remark upon today. Leeistad, my guess is that the reason Velodyne didn't succeed (in either sense, businesswise or sonically) with their speaker back in the mid-90's wasn't simply because they make subs per se, but because this was their ambitious first attempt at making a satellite speaker. More than one company hasn't succeeded with their first product in a category as well as they did farther down the road. Of course, Velodyne it seems subsequently decided not to proceed any farther down that particular road, so their failure is what I tend to remember (since I was supposed to be trying to actually sell these things at the time).
Moving from the specific to the general for a moment, let me throw this out there: It occurs to me, after reading the recent responses above, that the high-end nominees fall mainly into two catagories: Those with limited bandwidth, limited dynamic range, nonlinear tonal balance, and/or relatively high levels of harmonic distortion; and -- somewhat ironically -- those with wide bandwidth, wide dynamic range, relatively neutral tonal balance, and/or low levels of harmonic distortion.