The last W3C working group I participated in, Multimodal Interaction (MMI), is at the periphery of the Web and is unlikely to make much of an impact on it in the foreseeable future. However they have produced a few interesting specs (and a few uninteresting frameworks), one of which I will return to in much greater detail later.
The most obscure one may be InkML. The name might imply a language for tagging with paint, but is really describing the set of movements registered by a touch-sensitive tablet or screen so that the scribbles you make can be processed and enhanced by someone more clever than the tablet driver. Unfortunately this specification is made by a tablet-maker subgroup that like Schrödinger's cat is living or dead depending on your perception, and the spec is progressing at a less than vital speed. …