vpr-Matrix is a Best Buy-only brand. So, I would assume it's like CompUSA branded hard drives. Once you open the CompUSA box, there is a Maxtor drive inside.

Other than that, the only non-big name brand hard drive is probably Samsung. Not that they're a small company, but you don't assosciate them with hard drives. Before that was JTS (Atari), but I have not seen a drive from them in years.