I know this is subjective: what's the best personal robot?

This article (http://eengenious.com/coming-home-for-c … s-we-love/) selects five personal robots, all targeting different applications. I realize that “best” is a subjective judgement, but it may be that “best” applies to the application, not to the machine; in my view the best application for a personal robot is one that enhances (or substitutes for) human capabilities, not necessarily the one that makes the most money. This is a bit of a philosophical discussion on the “merits” and social value of technology, I know, but I’m very interested in the perspective of the Sparkfun community and the maker movement, as representative of sociological phenomena.