dotMP
.mobi would at least have been a cool bumper sticker. Now dotMP (think Mobile Phone) comes out with the same ideas -- encoding accessibility from mobile devices into the TLD string --, but without the bumper sticker effect.
See also: Device Independence
ObCorollary: Any possibly lucrative idea that can be implemented in the DNS will, at some point of time, be implemented in some ccTLD, regardless of its actual quality and harmless- or -fulness. Exercise: Apply this corollary to new gTLD criteria.