HP has acknowledged that it's been working on a Windows 8 tablet; it just hasn't mentioned whether or not the rumored Slate 8 is part of its plans. Imagine our surprise, then, when we're told that HP's 60-second "Make It Matter" commercial ends with an unannounced yet familiar-looking tablet right at the 56-second mark. There's only a fleeting glimpse, but it shows a metallic-looking body with a large black antenna window -- the combination of which would fit in with the Slate 8's purported aesthetics. We've asked HP whether or not this is a clever teaser for a real product or just as conceptual as the rest of the ad, and we'll let you know if we hear back on the subject. In the meantime, you can inspect the video evidence for yourself after the break.