The enterprising patent watchdogs over at Neogaf have unearthed two previously-undiscovered Sony patents—one, a sensor similar to Kinect, and the other, an add-on for next-gen consoles that would improve backwards compatibility (which has apparently been discussed by Sony before).
The first patent was filed late last year by Dr. Richard Marks, who invented the PS Eye and Move. It describes "a real-time three-dimensional interactive environment" and "a console having logic configured to render and display the objects placed through the particular depth range in a virtual scene based on geometric characteristics of the object itself." Basically, as others have pointed out, it sounds like Kinect (which itself was not exactly an original idea).
The second describes a "compatibility adapter configured for connection to an external connection terminal of a new-generation game device" in which "data extracted from a received packet is supplied to the old-generation processor unit and processed accordingly. The hub supplies the processed data to the new-generation game device via the external connection interface."
Basically, it seems to describe a peripheral that would allow, say, the PS4 to more accurately emulate the PS3 (and possibly, by extension, the PS2 and PS1). Nixing backwards compatibility from Sony's next console would bring the cost down for those who don't care about playing older games, and the add-on, for those who do care, would be cheaper than buying three other consoles. It's not a bad idea.
Could these be used for future Sony projects? No idea. But is it fun to speculate? Hell yes. Let us know your thoughts in the comments or on Twitter.